


No Light Thing

by philalethia



Category: Sherlock (TV)
Genre: Aftercare, Angst, Biting, Bloodplay, Bruises, Explicit Sexual Content, First Time, Insecurity, Kink Exploration, Knifeplay, Lack of Communication, M/M, Marking, Misunderstandings, Painplay, Past Drug Use, Pet Names, Possessive Behavior, Post-Season/Series 03, Sadomasochism, Scars, Scratching, Sherlock Loves John, Spanking
Language: English
Status: Completed
Published: 2014-09-11
Updated: 2014-10-13
Packaged: 2018-02-17 00:39:40
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 6
Words: 38,524
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/2290613
Author URL: https://archiveofourown.org/users/philalethia/pseuds/philalethia
Summary: <blockquote class="userstuff">
              <p>John wants a healthy relationship. Sherlock struggles to understand the concept.</p>
            </blockquote>





	1. One

**Author's Note:**

> This started as an attempt to write a story that wasn’t about kink. Somehow it turned into a story that both is all about kink and has nothing to do with kink. So… enjoy? :)

The night that John finally becomes _his_ , Sherlock lies beside him in bed for nearly an hour, simply observing.

Sexual satiation makes John drowsy, apparently. He lingers in stage one of the sleep cycle, always jerking awake before he can progress beyond it, then closing his eyes again and promptly returning to stage one. Stubborn, perplexing behaviour. It suits John perfectly.

Everything that Sherlock knows of John’s sleep habits he’s learned from deductions. It’s an impressive amount of knowledge, of course, because Sherlock’s powers of deduction are impressive, but it’s not the same as data that is observed—which he has now been given the opportunity to gather.

Sherlock never thought he could have this: John in his bed, drowsing contentedly only inches away, as though there’s never been any question that he belongs here.

Sherlock’s adoration is practically a physical presence in his body, a sort of parasite in search of an acceptable environment to colonise. In the years he has known John, his lungs have been affected, his stomach, his vocal folds, his brain, and of course his heart, which is affected now as he watches John wrinkle his nose and snuffle and turn his face into Sherlock’s pillow. Sherlock’s chest feels tight, his heart aching under the increased pressure.

Ridiculous, sentimental. There’s a whisper of Mycroft’s voice in his mind, but Sherlock shoos it away as he always does.

Beside him, John jolts from stage one again, but this time instead of returning to it, he rolls to his back and blinks at the ceiling.

“Sorry,” he says muzzily. “Didn’t mean to just—”

“It’s fine,” Sherlock assures him.

John stretches, his lower back lifting minutely off the bed. The bedsheets dip below his pectorals, exposing the tops of his areolae, but stop before the nipples themselves. Sherlock didn’t get to examine those earlier. He has no idea if they are sensitive, if touching them would make John arch in pleasure or grimace in discomfort.

“Ugh,” John groans, sitting up. “I need the loo.”

When he leaves, Sherlock feels like a train removed from its track: useless, directionless. He crawls into the now Johnless space on the bed and inhales deeply.

He smells John—cheap shampoo, musky aftershave, an Irish breakfast tea, and Mrs Hudson’s lemon tarts—but also himself, noticeable now only because of its contrast to John’s less ubiquitous scent. Fitting, Sherlock supposes. He is aware of himself most strongly when John is present.

The noise of John urinating filters through the closed door between the toilet and Sherlock’s bedroom. It’s surprisingly comforting. Sherlock wraps the sound around him like a cloak, burrows into the knowledge that John is mere metres away and coming back shortly.

Sherlock doesn’t retreat to his previous position, and it doesn’t occur to him that there is anything wrong with this until John returns and simply stands beside the bed, staring down at Sherlock as though he’s puzzled by what he sees.

His posture, his tense shoulders, suggests he feels awkward. His hands are curled in fists in front of his thighs, which are wet where he wiped his hands dry after washing them. He’s fighting the urge to cover himself, as though Sherlock didn’t have his mouth on John’s penis an hour ago.

At least, Sherlock reflects, he seems to realise the impulse is irrational.

“Erm,” says John, and his fists tighten. Sherlock is reminded of knots in a rope. Nooses. Cerebral hypoxia. “Not sure if you’d rather I bugger off upstairs or—”

“Stay.”

Sherlock doesn’t mean to say it. Well, he does, but not so straightforwardly. He is trying to decide how to take it back without actually _taking it back_ when John’s shoulders relax, his fists unknot, and he climbs back into bed. On Sherlock’s side, this time. Or at least what, five minutes ago, had been Sherlock’s side.

John wraps the sheets around himself and rolls onto his stomach with his head turned, facing Sherlock. His eyes close.

Sherlock will never be able to know every thought that passes through John Watson’s head. There is an entire world, fields of unfiltered impressions and mounds of partially formed ideas, that will never give themselves away in John’s expression, and thus Sherlock will remain ignorant of them. Unfortunate, distasteful, but out of his control.

“Mm,” John murmurs, his voice heavy with sleep. “Your pillows smell good.”

The parasite of adoration worms its way into Sherlock’s oesophagus, and he struggles to swallow around it.

 _If you leave me_ , he thinks, _I will crumple like a paper cup, not empty, not entirely, but close enough that there’ll be nothing for it but to crush and bin me like the other useless things._

But he says none of it, of course. Just concentrates on remaining still and quiet as John finally drifts into the second stage of sleep.

*

Sherlock makes tea the following morning so that when John is finished in the shower, a steaming cup—strong, no sugar, a splash of semi-skimmed milk, exactly as John prefers it—is waiting on the table.

John sits with a startled look—understandable, since Sherlock making tea without being bullied into it is nearly unheard of—but says nothing aside from a murmured “Thanks” as he scoots the cup closer.

Sherlock inclines his head and finishes making his own cup—also strong, two lumps of sugar, and rather more than a splash of milk—before he sits as well, taking in John’s appearance as he does.

Freshly showered, obviously, although his hair is already very nearly dry. John’s jumper is tidy, not a wrinkle nor speck of lint or hair to be found, and he smells overwhelmingly of toothpaste. An uncharacteristic amount of time and attention spent drying and grooming himself. Indicates nervousness, avoidance.

Then John clasps his hands with a sigh, interrupting Sherlock’s mental deductions, and says, “I’m having second thoughts,” and Sherlock understands devastation to a degree he had not thought possible.

And suddenly Sherlock is in the bedroom again, less than two hours ago when John’s cold toes tucked themselves beneath his ankle and John sighed in his sleep as though the whole world had been righted by that single unconscious action, and Sherlock wanted to build an entire room in his mind palace for this moment—and had done, and retreats into it now. Although now Sherlock isn’t lying in the bed, but drowning in it, waves cracking over his body like whips. Salt stings his eyes and water floods his throat.

Then he feels John’s hand on his arm, hears John’s voice saying his name again and again, and realises John is kneeling beside him, his face open and pale with alarm.

“Sorry,” he says, when Sherlock blinks dumbly at him. “Christ. That’s what I get for not thinking before I open my fucking mouth. I didn’t mean that like it sounded.”

“You’re having second thoughts,” Sherlock recalls. His lips feel numb. He is overreacting, he knows. He is acting every bit the drama queen that John has more than once accused him of being, but he cannot seem to stop.

“Second thoughts as in concerns, not regrets.”

“Concerns.” The word echoes in his mind like ripples in a pond. “What concerns?”

“Well, for starters, we live together. We’ve been friends for years. And not just friends, mind, but best friends. We’re colleagues. Adding sex, a relationship, it’s just—” John sighs, deep etchings of gloom on his forehead. “It’s a lot, and if something goes… badly, then we lose a lot.”

Those sound more like regrets to Sherlock than concerns. But he can see from the way John licks his lips, staring off over Sherlock’s shoulder, that he has more to say, so Sherlock remains quiet. Waits.

Finally, John says, “Not to mention, you know, the last long-term relationship I had wasn’t exactly rainbows and happily-ever-afters.”

Sherlock knows. Mary’s betrayal is the perpetual gap in John’s armour, her death the weight on his shoulders that makes his shadow loom.

“And,” John continues, “I can’t do that again. Especially not with you, Sherlock, I just… can’t. I want a healthy relationship. And we… I mean, we can have that, yeah?”

Have a “healthy relationship”? Sherlock tries to conjure an image of one, does a quick scan of all the dusty crannies of his mind palace, and finds nothing. Doubtful he can attain something if he has no point of reference.

Sherlock is bleeding. He’s gone into battle in nothing but his thinnest dressing gown and yesterday’s pants. Stupid. Stupid thing to do, of course John would have second thoughts, of course John doesn’t want to be romantically or sexually attached to another sociopath with no concept of a “healthy relationship.”

“Sherlock?”

 _Hide it_ , Sherlock thinks, _at all costs. Cover the wound, do not let him see that you are bleeding out right here in the kitchen over tea, you complete clot._

“Of course,” he says. Although panic still buzzes in his thoughts, his voice is calm, composed. “If anything, our history gives us an advantage. We’re flatmates—I know the worst of you, and you of me.”

Sherlock is still building the argument in his mind—quickly, stacking large stone atop large stone, hoping the weight will keep it all from toppling even if he hasn’t anything to hold them together—but John shakes his head before he can say anything further.

“It’s fine. I’m not really looking for some sort of defence. I just….” John licks his lips again, clearly giving his words a great deal of thought. “I just wanted to tell you my concerns. I was lying in bed this morning imagining all the ways this could crash and burn before it’s even started, and I don’t want that. I really, really don’t want that. So I thought, you know, importance of communication and all that—”

“Communication is part of a ‘healthy relationship,’” Sherlock guesses.

John nods, looking pleased, and some part of Sherlock hops about on its hind legs, happy to have got it right.

“Exactly. So if we’re going to give it a go, if we’re going to sleep in the same room and kiss and act like a couple and all that, I want to be sure we’re careful about it. Yeah?”

“Yes,” Sherlock agrees, and vows to be very, very careful indeed.

*

Both the OED and Dictionary.com define _healthy_ (adjective) as “possessing or enjoying good health or a sound and vigorous mentality” as well as being “conducive to health.”

Sherlock ponders that far more than any of the rubbish that searching “healthy relationship” on Google turns up. Endless articles tossing about words like “respect,” “trust,” and “equality” that Sherlock can’t fathom being of any help to anyone and certainly not to him. He’s a detective; he thrives on concrete data, not abstractions.

But, although the dictionaries are more direct and thus more clear, they aren’t especially helpful either.

After all, John needs danger. That hypothesis has been proven again and again throughout their friendship, as has the fact that John is drawn to Sherlock because of the danger of his work. But repeated encounters with danger are not “conducive to health.” Therefore, John cannot be seeking the sort of “healthy relationship” implied by the definition of _healthy_.

The contradiction creates an impasse. Sherlock spends an hour in front of the computer, dozens of tabs open in his internet browser, trying to push past it.

Fact: John wants a healthy relationship.

Fact: John’s relationship with Mary did not fit his definition of a healthy relationship, likely because Mary: 1) lied to him about her identity, 2) nearly murdered his best friend in order to continue lying to him, and 3) purposely withheld crucial information about her past even after supposedly coming clean.

Conclusion: To avoid contributing to an unhealthy relationship with John, Sherlock can never: 1) lie to John about his identity, 2) harm John’s friends, and 3) purposely withhold crucial information.

John no doubt is primarily concerned about the final item, since Sherlock has on occasion withheld crucial information (and, during one such instance, caused John two years of grief), but complying with all three is doable, Sherlock thinks.

And if there are other stipulations, Sherlock will surely learn about them in due time, from John’s comments on other couples or his comments on their own burgeoning relationship.

It’s fine. The bleeding is staunched, the wound sufficiently dressed and hidden. As long as Sherlock is careful, as John said and as he intends to be, everything will be fine.

*

Sherlock moves John’s clothes from the upstairs bedroom into the downstairs one. In part because he knows John would not appreciate being left to do it all himself, and in part because the idea of John’s belongings continuing to exist so far from Sherlock’s is abhorrent.

Besides, John said _‘if we’re going to sleep in the same room.’_ And they’ve slept together in Sherlock’s room every night since then, even during the nights when Sherlock doesn’t actually sleep but instead lies motionless beside John and breathes him in like a cloud of cigarette smoke. So it would be absurd to continue keeping their clothing on different storeys of the flat. Sherlock is certain of this.

He has to throw out several shirts, four pairs of trousers, and a selection of socks and pants to make room for all of John’s clothes in his wardrobe and chest of drawers. But he considers it a worthwhile sacrifice just to be able to see John’s jumpers hanging beside his own dress shirts, John’s pants nestled in a drawer with his own.

“Did you do something to all my clothes?” John asks that evening, standing in the doorway to Sherlock’s bedroom while Sherlock undresses for bed. His tone says he knows the answer to his question but for some reason wants to hear Sherlock verbalise it.

Sherlock obliges. “Moved them down here with mine. It hardly seemed practical, you continuing to climb the stairs every morning to get dressed and every night to get undressed if you’re to continue sleeping down here.”

When John’s first response is to blink owlishly and peer at Sherlock as though he’s done something utterly unfathomable, it occurs to Sherlock that he might have been wrong-footed after all. The word _unhealthy_ flickers in and out of his thoughts.

But John doesn’t appear upset or angry, just taken aback. “Oh,” he says. “Thanks.”

Sherlock relaxes and settles down on the bed, watching John paw through the drawers and sift through both Sherlock’s clothes and his own in search of his pyjama bottoms.

The rush of the pleasure he gets from the scene is immense, more potent than cocaine, and it lingers for days.

*

John has birthmarks on his right thigh, his left calf, and the big toe of his left foot: all caramel-coloured, circular, uninteresting except for their potential use as identifying features.

He also has a mole on his back to the right of vertebra T10, and another a bit lower where the waistband of his pants sits just above the swell of his arse. Individual freckles dot his legs in various places, and there’s an isolated burst of them on his right bicep.

There’s a faded scar on John’s left ankle: a pale two-centimetre-long sliver where it appears the top layer was stripped from his skin. “Harry dared me to shave my legs when I was about eight,” John says when Sherlock asks. “Pressed too hard and shaved off a bit of skin. An awful mess, that was.”

There are also dozens of other tiny, barely noticeable scars that John is apparently ignorant of. Sherlock pokes at a miniscule patch of discoloured skin behind his knee, on the top of his foot, just below his ribcage, and John shrugs, utterly unconcerned, and says, “Dunno. Could’ve been anything, really.”

And then, of course, there’s _the_ scar on his left shoulder. Shot from behind by a sniper several metres above him. The bullet passed through his shoulder, shattered the bone, and grazed the subclavian artery. It became infected afterwards, quite badly so, and left the skin gnarled and mottled. The scar is large, “ugly” according to conventional ideas of attractiveness, somewhat resembling a fat spider waiting at the centre of its web, but Sherlock adores it beyond measure.

Sex becomes an exercise in worshipping it. When he gets John’s shirt off, Sherlock likes to climb on top of him and kiss the scar, run his tongue over the damaged skin, and suck gently at the raised scar tissue, colouring it an angry pink.

Time slows. Sherlock’s face grows wet with his own saliva, his body aches from being bent over so long, and beneath him John becomes a squirming, panting obstacle to his exploration.

“Christ,” John says through clenched teeth. “If you could, maybe, put your mouth a bit lower—or your hands, I’m not fussy—”

Sherlock does better, and slicks up his arse so he can sit on John’s cock.

John’s penis is average-sized, albeit much larger than Sherlock’s, with only the slightest upwards curve of the shaft and loose, pliable foreskin. Certainly not intimidating by sight, but to have it inside him… it feels huge, thick and long and hard as steel. And John—well-mannered, supremely cautious of hurting Sherlock—goes still and pliant while Sherlock adjusts, giving Sherlock the opportunity to touch and taste his scar without interruption.

Even when Sherlock gives in and starts to ride him, keeping to small stuttering motions so he doesn’t completely lose himself in the pleasure of it, John remains mostly still, staring up into Sherlock’s face with his eyes and mouth wide with awe.

Sherlock paws at his shoulder, lifting it a little so he can stroke the entrance wound. He pictures the bullet’s trajectory, the near-instantaneous fracture of flesh and bone, the continuous spill of blood afterwards. He doesn’t believe in miracles, of course, but this—that John survived to meet Sherlock and kill for Sherlock and let Sherlock sit on his cock and admire his scar—is the sort of thing that must make others believe in them.

He still hasn’t got his fill of the scar when John is shrugging off Sherlock’s grip and surging upwards, flipping Sherlock rather impressively onto his back. John’s cock slips out in the move, although Sherlock barely even manages a groan of disappointment before it’s being pushed back in.

“All right, enough of that,” John says with a laugh. “You can play with my scar all you want after we’re done.”

Acceptable, Sherlock decides, although he suspects he’ll still have to settle. _‘All you want’_ is… rather a lot. He wants to know John like no one else ever has, and to have him in ways John has never let himself be had.

John is staring down, watching his cock disappear into Sherlock’s arsehole, with an expression of such rapture and captivation that Sherlock feels like a treasure, golden and rare. He bends his knees and brings them to his chest, baring himself as much as possible, inviting John to keep looking at him like that, to _always_ look at Sherlock like that.

“Anything to say before I fuck you into this mattress?” John asks, still staring.

“Please,” Sherlock answers, and within seconds, he’s being fucked so hard he can’t form words at all, only deep grunts and throaty “uh, uh”s while he drops his knees and does his best to wind his entire body around John like a vine.

He wraps his legs around John’s waist and tugs him down so he can cling to John’s shoulders, muffle his cries in John’s neck. The penetration is shallower this way, the angle more awkward and possibly (Sherlock realises a moment too late) less satisfying for John, but John allows it, holds Sherlock close even though it means he can’t thrust properly, that he can only hump at Sherlock’s arse like a dog.

Several times, the crown of his cock catches on the rim of Sherlock’s hole, nearly slipping free again before John manages to shove it back in, filling Sherlock with the never-ending burn of that initial penetration, the feeling of _so full_ and _too much._

“That’s it, love,” John tells him, panting. “God, I’m so close.”

It’s the “love” that does it. It breaks Sherlock open, reduces him to wailing helplessly into John’s throat and clutching desperately at his sweat-wet back. It’s perfect. It’s so perfect it hurts. It cuts him like a strip of silk.

After Sherlock has come—long after John has, with John’s mouth on his cock and John’s come leaking from his arse—John goes to fetch a wet flannel while Sherlock drifts, half-dazed.

The term “afterglow” is, for Sherlock at least, an utter misnomer. His post-coital physical and mental states aren’t glow-like at all, but instead rather dim, like a dense cloud of smoke. He lies cradled in its murk, listening to John rummage through the bathroom cupboard.

“Christ,” John says suddenly. There’s a flinch in his tone that promptly scatters Sherlock’s afterdim. “You scratched me.”

Sherlock is on his feet in an instant, hurrying to investigate. He finds John peering over one shoulder into the mirror. Someone has indeed left a series of long scratches on his back, and although Sherlock has no memory of doing so, the position of the marks—the space between them matching perfectly the space between Sherlock’s fingers when his hands are splayed—proves that he did.

Sherlock comes closer, spellbound by the sight: the raised pink lines on either side of John’s spine like wings, beginning just below his scar. John allows Sherlock to swivel him round and examine them. There is no blood, no indication of lasting damage, although they are puffed-up and irritated, the top layer of epidermis scraped off. Sherlock looks at his hands and find flakes of it beneath his fingernails.

The evidence of Sherlock’s ecstasy has been written on John’s skin, as real as the bullet wound on his shoulder, albeit less permanent. Satisfaction swells between Sherlock’s ribs, curls around his sternum.

He trails his hands down John’s shoulders, lifting his palms before he reaches the marks so he is simply tracing the shape of them with his fingers, envisioning how they were made. When Sherlock was clutching John’s shoulders, senseless with pleasure—as was John, apparently, since he’d not known until just now that he’d been scratched.

Sherlock realises that it is perhaps not good—even _unhealthy—_ that the sight of John injured by Sherlock doesn’t inspire horror or regret, but satisfaction that runs as deep as the Thames. In fact, he should apologise for scratching John, however inadvertent it had been. That’s what normal people do, isn’t it? Apologise when they’ve hurt someone?

He takes his hands away and rubs them awkwardly against his thighs. “Apologies. I didn’t realise that I’d… that is, I had no—”

John laughs, the sort of laugh that Sherlock typically enjoys—it means that Sherlock has succeeded in bringing a beam of light to his thoughts, as John often does for him—but this time the sound only puzzles him.

“It’s fine,” John says, shaking his head as he half-turns. There is genuine delight in the wrinkles at the corners of his eyes. “Kind of nice, actually. Being hurt during sex, that is.”

 _I can hurt him in a sexual context_ , Sherlock thinks, surprised, _and it is, apparently, acceptable._

After filing that away for further consideration, he leads John eagerly back to the bed and proceeds to eat John’s arsehole for over an hour, until John’s cock is hard enough for another go. Then he climbs on top of it and rides it until John is moaning and shaking and gripping Sherlock’s hips like a vice, like not even death can convince him to let go.

*

Lestrade summons them to a crime scene the following morning. A child gone missing during the night, her bedroom in violent and blood-spattered disarray: suspected murder.

It’s dull. Obvious. Sherlock has a fairly good idea of what happened from just speaking with Lestrade over the phone, but arriving at the scene, seeing a photograph of the missing girl while the distraught parents stand huddled together and weeping, confirms it.

“Abducted by her birth father,” Sherlock says, handing back the photograph. “Who, I suspect, didn’t realise until very recently that he had a child. Hence the abduction. She was probably injected with a strong sedative and then a portion of her blood removed by syringe. The blood isn’t so much spattered as it is dripped strategically, and not even the most violent struggle would be enough to tip a desk of that size entirely over. Apart from the blood loss, he’ll have left her unharmed.”

“Birth father!” the man says, looking dumbfounded. His tears seem to have frozen on his face. “What—”

“In terms of eye colour, brown is the dominant gene,” Sherlock says. “You and your wife have blue eyes, but your daughter has lovely brown ones. They had to have come from somewhere, and they certainly didn’t come from you. So: birth father. You know his name, I assume?” he asks the mother, who gives a small nod, staring very determinedly away from her husband. “Excellent.”

Case solved. Simple. The police need only get the man’s name from the mother and then locate him. Sentiment has made him stupid; he won’t have gone far from his own home, if he’s even left it at all. Sherlock’s assistance isn’t needed any longer, nor does he want to provide it. Kidnapped children are not cases that he enjoys, certainly not after the last one.

“Jesus,” says Lestrade, while the crowd of surveying police officers flutters into motion around them. “That was…”

 _Child’s play_ , Sherlock thinks. _Hardly worth my time, and nothing your team shouldn’t have been able to manage._

But John is beside him, a soothing presence, and Lestrade looks harried, unshaven and over-caffeinated—under a great deal of pressure to solve this quickly, either mother or father is related to someone important at the Met—so Sherlock says nothing. Besides, there’s still the matter that brought him here, even when the case held no appeal and was mostly solved before Sherlock had even put on his coat.

“Quick,” John offers, filling in Lestrade’s silence.

“Might’ve been a new record, yeah,” Lestrade agrees. “Thanks. We can take it from here, I think.”

Lestrade rubs his face with a sigh and then— _yes—_ looks at Sherlock.

Sherlock waits.

There are, he knows, countless indicators of the change in his and John’s relationship currently visible on their persons:

John carries himself stiffly, avoiding large spine and shoulder movements so he doesn’t irritate the still-stinging scratches on his back, and Sherlock has the careful, not-quite-limping gait of a person who’s just enjoyed multiple rounds of vigorous anal intercourse.

John smells clearly of Sherlock’s shampoo, has scuff marks on the knees of his trousers and stubble burn on his neck, and his hair has the dishevelled, faintly oily appearance of having been repeatedly stroked, grabbed, and tugged.

Not to mention, John’s lips—and, he presumes, his own, although he can’t see them at present—look freshly kissed, the wrinkles on his collar indicate he’s recently stretched his neck to reach something taller than him, and the lapels of Sherlock’s coat still bear indentations from the grip of a strong, insistent pair of hands.

Yet Lestrade’s gaze lingers on none of these details. In fact, Lestrade doesn’t seem to notice them at all.

“Sherlock,” John says, touching the sleeve of Sherlock’s coat. It’s a tender, familiar touch. A dead giveaway on its own that Lestrade again fails to see.

Disappointment, bitter as low-quality coffee. Lestrade won’t mark the frankly momentous change without assistance, apparently. Less subtle, then.

How best to introduce it into conversation?  _John Watson, my…?_

Oh, Sherlock realises. They haven’t discussed appropriate labels.  _Boyfriend? Lover? Partner_ seems the most accurate, encompassing the whole of their relationship, but it is also the most ambiguous. Not ideal.

“Sherlock,” John says again, this time a hint of steel in his tone. “Greg said they can handle it.”

Sherlock notices now that Lestrade’s eyebrows are raised, his expression becoming one of faint alarm under Sherlock’s steady stare. Beyond him, Donovan is speaking with the mother, who is crying more softly now, while her husband paces a short distance away. Yes, Sherlock is quite content to let Lestrade’s team deal with that. Sherlock can alert them to his new status as John’s boyfriend-lover-partner another time.

So he allows John to lead him from the house, his hand still gripping Sherlock’s sleeve.

On the pavement outside, John finally lets go with a sigh. “That went a little quicker than I’d imagined.”

He looks distinctly put-out by that, and a splinter of guilt wedges itself in Sherlock’s thoughts. He really needn’t have come, he supposes. All he’s done is shower sparks on John’s incredibly flammable danger addiction only to then stamp the fire quite effectively out.

But before he can respond, John shakes his head and continues. “Ah well. That was brilliant, by the way. You knew from half a glance at one photograph that that man wasn’t her biological father.”

Of course Sherlock did. It was obvious, wasn’t it? One needed only a basic understanding of genetics to see it, which John certainly possesses.

Still, pleasure blooms like bacteria at the praise. Sherlock’s skin feels warm, his head light, and he has to drop his chin to stop the toothy, insipid grin that threatens to form.

“Coffee?” John asks, nodding to a Starbucks across the street.

It’s not their usual post-case fare, of course, but perhaps chips at not quite half ten aren’t practical.

“Yes,” Sherlock says.

The Starbucks is crammed with people, the queue so long it winds between the tables. John, always uncomfortable in a crowd, stands close to Sherlock. Their arms press together from shoulder to elbow, and Sherlock would only need to turn slightly and bend forwards to curl around him.

For several minutes, Sherlock allows that thought to linger. Imagines himself as the earth to John’s sun: drawn to him, warmed by him.

 _Would you find it objectionable_ , Sherlock thinks, _if I referred to you as my boyfriend? Even if it’s not your preferred label, you’ll surely agree it’s not inaccurate, yes?_

He pictures the shape of the word on John’s lips. Easy to do after years of John hedging around inquiries about Sherlock’s sexuality and romantic history. Like that first dinner at Angelo’s. _‘Do you have a boyfriend?’_

“A bit sad, wasn’t it?” John says, jarring Sherlock unpleasantly from his thoughts. “The case, that is.”

“Sad?” All of Sherlock’s cases could be considered “sad,” this perhaps even _less_ so than the others. After all, the mystery is solved, the child will almost certainly be returned without significant harm, the parents— “Ah. The mother’s adultery, you mean.”

John’s lip turns down, and he inclines his head. “Yeah.”

The queue moves quickly, and they shuffle forwards along with everyone else while Sherlock considers his response.

John’s unfailing loyalty is, in Sherlock’s estimation at least, among his most notable qualities. Of course the idea of a person cheating on their spouse is upsetting to him. Offensive to his very solid moral principle. If his marriage to Mary were any indication, John himself would remain faithful no matter how dysfunctional and unfulfilling the relationship had become.

That thought gives him pause, lingers in his mind like a blood stain on white.

“Sherlock,” John says, nudging him forwards, and—oh. The queue has moved again, putting them nearly at the front of it.

“What can I get started for you?” a barista asks. Short, blonde-haired, female, midtwenties, and terribly chipper. Not significant enough to observe beyond that, so Sherlock pays her little attention as he places his order.

“Just a filter coffee for me. Tall. And—” He considers John: expression, posture, the quality of his sleep the previous night, and of course his personal taste. “—espresso macchiato for him. Semi-skimmed, just the one-ounce shot of espresso. Tall as well.”

“Exactly what I had in mind. Brilliant sod,” John says with a smile, and again Sherlock has to duck his head to avoid returning it.

Sherlock pays, then watches John while they wait for their drinks to be made. He’s adopted a parade rest position, although he appears anything but at rest. His jaw is clenched, his shoulders tense, his gaze darting from person to person. Sherlock wonders if he even consciously realises he is scanning the coffee shop for threats, or if it is purely instinct, as ingrained in him as the need to blink.

When their drinks are finished, handed to them by the same chipper barista who’d taken the order, they sit at a two-person table to the left of the entrance. It’s small enough that their knees knock against each other, and when John takes the touch a step further and interlocks them, one of Sherlock’s knees between his and one of his between Sherlock’s, affection makes a thick knot in Sherlock’s throat.

 _If it wouldn’t disturb you or get us thrown out,_ he thinks, _I would crawl beneath this table and lay my head on your knee._

Then John snorts in amusement and spins his cup round so Sherlock can see there is writing on it.

A phone number, to be precise. Then, below the number: _Geri_ ♥

“I can’t remember the last time I got one of these,” John says. One side of his mouth is still quirked up in amusement, although Sherlock sees very little that is amusing about the situation.

“A woman’s number?”

He sounds jealous, he realises, although he isn’t. Of course he isn’t. Why would he be? The barista—Geri, evidently—is too young by John’s standards, and in any case, he’s already established that John is loyal. So loyal in fact that even if some part of him _wanted_ —

 _No_ , Sherlock thinks, _not now._

Rather, he is concerned more with the fact that again someone has missed the _very obvious signs_ that John is neither romantically nor sexually available. Sherlock mentally relives his and John’s time in the queue. Sherlock ordering and paying for John, John standing closer to Sherlock than is socially acceptable for just friends, John’s body angled in Sherlock’s direction.

Alarming that she missed them, although not as alarming as Lestrade missing them as well. That his and John’s relationship isn’t written on their bodies like Sherlock thought—hoped—it was. That his biases are influencing his observational skills. That at this moment a pretty barista named Geri is envisioning that John might return her interest, that she will soon be sitting in her flat with her two dogs, no, her dog and her flatmate’s cat, when her mobile rings—

“—at her if you could, thanks,” John is saying, and the world outside Sherlock’s mind blinks back into focus. He meets John’s gaze, and John smiles a bit stiffly. “All right?”

 _Of course_. That is what Sherlock should say, obviously, and what he means to say. But instead, he answers, “They can’t see. Lestrade, the barista, no one has been able to see that you… well, that is, that you and I—”

“Well, not everyone’s a genius like you.” John shrugs as though it’s of no consequence. As though it doesn’t matter a whit to him if strange women continue to give him their numbers or his friends fail to recognise his new relationship. “Although, to be fair, I think the barista’s figured it out by now. You’ve spent the last two minutes glaring at her like you want to set her on fire.”

Has he? Sherlock doesn’t remember that at all, but he must have done. When he glances at her now, he finds her looking considerably less cheerful than before and seeming quite determined not to look in their direction at all.

“Ready to go?” John asks.

In fact, Sherlock has done little more than set his cup on the table, and John certainly can’t have already emptied his either. But they hardly need to stay here to finish them, he supposes, so he nods, and they leave.

And when John does finish his coffee, he promptly bins the empty cup, and the barista’s number along with it. Sherlock makes sure of that.

*

John favours oral sex, in terms of both giving and receiving. Not strongly—manual sex, intercourse, and frottage satisfy him just as well—but enough so that his preference is as obvious to Sherlock as his military background.

This suits Sherlock perfectly fine. To have his cock sucked or his arse licked is enjoyable, albeit no more or less than any other sexual act, and there is little he loves more than spreading John out like a map and trailing his tongue over the ridges and valleys of John’s body.

For instance: John’s back, now. Sherlock can see the bones and muscles shifting beneath the skin like tectonic plates as John squirms, arches, tries to coax Sherlock’s mouth where he wants it. Sherlock laves his scar and then licks down John’s spine, counting each vertebra as he passes over it, imagining he is capable of touching the spinal cord itself, so vulnerable despite being so protected. He would keep it safer than his most sensitive experiment.

And then, because John is impatient and greedy, Sherlock dips between John’s thighs and eats his arsehole, suckles at his testicles, until John’s need is satiated enough that Sherlock can explore another minute or two uninterrupted.

Later, after John has come down Sherlock’s throat, John rolls to his side, boneless and drowsy with contentment, and nuzzles senselessly into the pillow while Sherlock curls around his back and measures the space between each of John’s ribs with his fingers.

“Disappointed that they’re gone?” John asks in a half-slur, rocking lazily back into Sherlock’s own cock, which is hard but not distractingly so.

Sherlock lays a tender kiss to John’s scar. “Hm?”

“The scratches you left on my back. Are you disappointed they’re gone?”

They’ve not faded entirely, actually, although the marks are so faint—thin streaks of skin only very, very slightly darker than the rest—that they might as well have done. It’s only because of the time that Sherlock has spent charting John’s back up close, and that Sherlock knows what to look for—in fact, he has the pattern of them stored permanently in his mind palace, and traces it behind his eyelids as he falls asleep—that makes them noticeable to his eye.

But John’s question….

“Why would I be disappointed?”

John turns. Tries to, anyway, although Sherlock is lying so close and holding him so firmly that the only part he manages to turn is his head. There’s a bit of dried drool at the corner of his lip, which Sherlock kisses wetly away.

“Because they were marks that you made,” John says, in the same voice as when he unearths some new element of popular culture to be astounded that Sherlock isn’t familiar with. “Because you’re a possessive git and you _marked me_ and, erm, you’re looking at me like I’m crackers now, so…. Never mind.”

John settles back down, looking abashed. His ears pinken faintly.

His embarrassment is utterly unwarranted—even though he was mistaken, he’s just given Sherlock an idea.


	2. Two

Over the next several days, the idea blossoms like a drop of blood in water, colouring the whole of Sherlock’s thoughts.

He researches, spends hours in his armchair plotting out the specifics in the safe confines of his mind palace, so that the next time he has John beneath him—on the sofa this time, where John likes to be straddled and snogged senseless—he’s suitably prepared to summon his most dark-eyed, lust-drunk expression and say, “I want you to hurt me.”

Sherlock expects John to freeze, pull back, and demand to know why he would want such a thing. Sherlock has written an entire speech to give in response, rubbish about how he’s dreamt of it for years but never felt comfortable enough to ask for it, until now, until _John_.

Instead, John’s hands frame his face, and Sherlock’s bottom lip is kissed once, twice, before John withdraws. His demeanour is calm, unflustered, when he says, “Mm. Hurt you how?”

 _How?_ It doesn’t matter how. Hit, scratched, burnt, Sherlock only cares that it is somewhere visible. Somewhere that can be easily revealed at a crime scene, in a coffee shop, at Bart’s, on the Tube, so that everyone can see that he’s been marked by John and know precisely what that means.

 _How?_ Sherlock shakes his head. Anything, he’ll accept anything. Any piece of incontrovertible evidence that John has chosen him.

“I could try biting you,” John murmurs. His thumbs sweep up and down Sherlock’s cheekbones, and then one falls to the junction between Sherlock’s neck and shoulder, shoving the shirt collar easily aside. “Around here, maybe. How does that sound?”

John’s teeth sinking into Sherlock’s skin, leaving behind a perfect impression. Bite marks are conspicuous, easily identifiable. As long as Sherlock doesn’t turn up his coat collar, forgoes his scarf, and is careful about what shirts he wears, it will be visible.

If Sherlock saw a man with a bite mark on his neck in full view, he would assume, in the absence of other data, the man’s partner is possessive: keen to _mark_ the man as their own, desperate to keep him.

That John will only do so because Sherlock specifically requested it is… well, perhaps he can delete that bit. Pretend that John’s desire for him is so strong it’s left a physical imprint on Sherlock’s skin.

“Yes,” he says, breathless at the thought. His skin as a mould for John’s teeth. His body as a temporary source of John’s dental records.

John hums agreeably, nuzzles softly at Sherlock’s neck, then closes his mouth around a tiny bit of skin and bites down.

It’s more of a nip than a proper bite, mostly painless and certainly not likely to leave a lasting mark. It’s also over in a single second. Then John is pulling back, licking his lips.

“Harder,” Sherlock says, dipping his voice low and accentuating his breathlessness. Appealing to John’s lust, his memories of Sherlock on his back begging for it harder.

John’s pulse spikes. Sherlock can feel it, just as he can feel John’s breathing quicken, and then he is being bitten again—properly this time, and with a hint of suction as well. The pain is startlingly sharp, reminds him of being pricked by a knife tip.

The image that follows is oddly thrilling: John holding a knife to Sherlock’s throat, blood beading along a fresh cut and spilling over, dribbling down John’s hand. Sherlock’s very lifeblood staining John’s skin. The idea is so appealing it’s almost irresistible. John is a doctor, after all, and a former Army one at that—he’s been covered in the blood of countless strangers, so why shouldn’t Sherlock have the same distinction?

When John pulls back, there’s a thin string of spittle on his chin, and his lips are parted enticingly.

“All right?” he asks, in barely a whisper. “Was that too hard?”

Sherlock shakes his head, then tips it back to expose more of his throat. “Again. Please.”

By the time that Sherlock has had enough—by John’s standards, that is, Sherlock is fairly certain he could withstand a lot more—the whole surface of his neck aches, and his mind churns like a failing machine, his thoughts coming in fragmented bursts.

“Was that all right?” John asks, hands on the back of Sherlock’s thighs, rubbing his palms mindlessly against Sherlock’s trousers. Wanting to move upwards and grope at Sherlock’s bum, but holding back. Uncertain.

Sherlock realises that although his own cock has gone limp under the onslaught of pain, John’s has not. He can feel it: tenting John’s trousers, pressing insistently into Sherlock’s groin. He rocks against it, testing, trying to gauge if he wants it.

His prick doesn’t even twitch. Not in the mood.

No, Sherlock doesn’t want to get off. He wants to bask in the faint, throbbing hurt from John’s bites and the sensation of John beneath him, content to be caged by Sherlock’s weight. John’s hands on him, Sherlock’s body belonging entirely to John. John’s cock hot and thick between them, John craving Sherlock just as much when he’s flaccid and pained as when he’s hard and pleasured.

_Except…_

John is aroused and unsatisfied, momentarily forgotten in the wake of Sherlock’s desires.

 _Stupid_. If Sherlock is selfish, he’ll fare no better than Mary at this rate, in terms of ensuring John’s continued affection.

With effort, he summons the energy and presence of mind to rock his hips again, this time more forcefully and with clear intent, and John drops his head back against the sofa with a quiet stuttering moan that makes satisfaction curl round and round Sherlock’s belly. He rocks once more, adding a sluttish little wriggle that he knows will make John think of penetration, of Sherlock writhing on his wet cock.

And then Sherlock is quite suddenly on his back on the floor, his shoulder blades aching dully, and John is following him, crawling between his bent knees.

“Sorry,” John says with an embarrassed grimace. “Sorry, that was meant to be a touch gentler, but… um.”

Sherlock doesn’t know what he looks like, precisely, except that he’s on his back and fully clothed, but it must make for quite an alluring picture, because John stares down at him like he’s a miracle, not only improbable but impossible as well, and then fairly falls on top of him with a muttered “ _Christ_ ,” kissing Sherlock’s jaw and chin and lips.

Sherlock opens for him, lets himself be pinned against the floor and snogged until he’s lightheaded and panting, clinging to John, his prick finally beginning to take an interest in the proceedings as John grinds against it, making muffled desperate noises into Sherlock’s mouth.

It’s ill-advised, he knows, to rut against each other whilst they’re both still clothed—it invites all manner of chafing and stains—but Sherlock hardly cares.

Especially when John abandons his lips in favour of pressing hot, wet, open-mouthed kisses to Sherlock’s throat where the skin is sore and tender and even still stinging in places. Reminding Sherlock vividly, wonderfully, of the bruises forming. Capillaries broken, blood leaked out, likely is even still leaking out as John kisses the bitten skin. Just a few layers of tissue preventing Sherlock’s blood from smearing onto John’s tongue.

“Fuck me,” Sherlock says, feeling lost and stupid under the swift and staggering rush of arousal. He arches, giving John full access to his throat, and wraps his legs around John’s hips. “Please, fuck me, _oh_. God, please.”

He comes like that, clawing at the back of John’s shirt. His orgasm is fast but weak, and afterwards he lies still and gasping as John finishes on top of him.

*

The bite marks bruise even better than Sherlock hoped.

He goes to sleep with dark reddish blotches, and he wakes to varying shades of blue and violet and obvious indentations of human teeth that are very nearly black in colour.

He spends an indeterminate amount of time in front of the mirror, admiring them. Wishing his phone or, even better, a proper camera was within reach so he could snap a photo. They are striking. They are brutal. They are beautiful.

His delight is a cadaver in water: gradually bloating, floating to the surface.

Then John wakes and stumbles into the loo for a piss with all the grace and consideration with which he handles Sherlock’s experiments just before he bins them, and Sherlock’s perfect morning is shattered.

“I am _fine_ ,” he says, sitting at the kitchen table whilst John hovers and frets as though Sherlock is in danger of dying from a few bruises and love bites.

 _Love bites._ Just the word makes Sherlock swell and shiver. His chest feels as though it will burst.

 _You indicated it was acceptable to be physically harmed during sex_ , he thinks desperately. _Now it is not. Why?_

“I don’t care if you’re _fine_ ,” says John. There’s a miasma of disappointment and regret so thick around him that it clogs Sherlock’s nostrils and sticks uncomfortably in his throat. “Jesus Christ, Sherlock, have you seen yourself? You look like you’ve been mauled.”

 _Mauled_. Oh, that’s a lovely thought. John atop him like an animal, Sherlock’s blood on his skin. Certainly an appealing image.

Why is it appealing? Should it be appealing? Perhaps not. Sounds a touch _unhealthy_ , Sherlock supposes. Precisely the sort of thing that might make John rethink their relationship. So he shoves the idea hastily aside.

“If you’ll recall,” he says, “I asked for it. You obliged me.”

Looking even more distressed, John shakes his head and sits down beside Sherlock. He scoots the chair close, until he’s practically in Sherlock’s lap, and then forces a towel-covered ice pack into Sherlock’s hands.

“Here. Does it hurt?”

It does, a bit, when Sherlock moves his neck. The skin feels stretched, tender. However, it’s hardly excruciating or even distracting, and what benefit Sherlock is meant to be gaining from an ice pack is beyond him.

So he tosses it to the table and promptly forgets about it.

“I scratched your back,” he reminds John. “When I tried to apologise, you told me it was ‘nice.’”

John shakes his head again. His expression is as dark as a crypt. “Yeah, but I didn’t mean to bruise you this badly. I didn’t even realise I _had_ bruised you this badly. I wasn’t paying attention and got carried away. That’s… that’s not good, Sherlock. If we’re going to play with biting and pain, then me not paying attention to how hard I’m biting is very, very not good.”

Sherlock nearly points out that he didn’t mean to scratch John either, nor did he realise he’d done so until after, so this is really no different. But then the whole of John’s meaning sinks in, and he becomes distracted.

“You didn’t mean to, which is not good,” he says slowly. His mind spins and whirs. “But if you had meant to, that would be… all right?”

Nodding, John reaches across the table to retrieve the ice pack and tugs it by the frayed corner of the tea towel towards himself. “If that’s the sort of thing that gets you off, then sure. Course, we’ll need to talk about limits, set boundaries, and maybe come up with safewords, but after all that… yeah, it would be all right. Now hold still.”

Then John forces the ice pack to Sherlock’s throat, on the bit of skin just above his carotid artery where the darkest, largest bruise is located. By now, the tea towel is nearly as wet and cold as the ice pack it carries, and Sherlock flinches with a hiss at the shock of it.

“Shh,” John says, and draws even closer, winding his free arm around Sherlock’s shoulder and stroking the hair at his nape.

The action is clearly intended to be soothing, and… well, it is, a bit. Sherlock can smell John’s unwashed skin and morning breath, and he wants to huddle close and bask in John’s presence, his attention.

“It’s all right,” John continues. His voice is soft, featherlike, and his fingers toy with Sherlock’s curls. “Just keep this on for a bit, sweetheart.”

 _Sweetheart_. Pet name. Indication of affection and familiarity. John has never called Sherlock “sweetheart.” In fact, to Sherlock’s knowledge at least, John has never called anyone “sweetheart.”

“It’s been a while,” says John, “but if I remember right, arnica cream’s what people recommend for things like this. I’ll see if I still have some.”

Sherlock neither knows nor cares what arnica cream is. He can feel the full weight of John’s affection settle on him like a thick, warm quilt, and he wants to savour its heaviness.

 _Call me it again_ , he thinks. _Call me it while you sit on my cock and look at me like you’ll never want anyone else_.

“See,” John says, a smile in his voice, and Sherlock realises he’s closed his eyes and tipped his chin up, giving John full access to his bruised and bitten throat. “This is what you should’ve got last night, if I hadn’t been such a berk.”

 _Is it?_ Sherlock thinks. _Interesting._

But he says nothing. His mind is mostly quiet, content: a cat reduced to purring by its owners touch.

*

The ice makes no immediate difference in the appearance of Sherlock’s neck, nor does the arnica cream. The bites and bruises remain just as blue and violet and blackish, although John’s expression does gradually lighten as the morning goes on.

By evening, he is finally grinning about it.

“Christ, you’re like a fucking peacock,” he says, seated in his armchair with his computer and watching Sherlock, who is pacing, restless, satisfaction rushing through his blood like a potent stimulant. “Preening. You know you look at yourself in the mirror every time you pass it?”

Does he? Sherlock hasn’t noticed, although he does highly approve of his own appearance. A good number of the marks are hidden by his shirt collar, but just as many peek out from beneath it.

He looks owned. He looks as though he has a bitey, possessive partner. He looks deliriously pleased about it.

That Lestrade’s not phoned with a case, that Molly is on holiday with her fiancé in Italy, that Mrs Hudson has—due primarily to the building’s thin walls and floors—already been apprised of their new relationship, is hateful.

“If I’d known you were this keen to be hurt, I’d have done it ages ago.”

“And you’ll do it again?” Sherlock asks, just to be sure.

John’s answering smile bares his teeth. _Those were in my neck_ , Sherlock thinks in awe. _You marked me with those._

“Yeah. If you want,” says John. “I’ve nothing against a little pain during sex.”

Sherlock does want. He wants any hurt that John will give him. Bites, bruises, even cuts—scars, permanence. Like the bullet wound in Sherlock’s chest, still visible long after Mary has gone.

“Yes,” he says. “Obviously.”

*

 _Aftercare_ is the term, apparently, for what Sherlock “should’ve got last night.” The hair stroking, the “sweetheart” bit, everything that made Sherlock feel brilliant, momentous—even more so than usual.

He discovers this while looking up _safeword_ on the internet and learns several other terms as well: _BDSM, sadomasochism, subspace, topdrop._

He encounters several sources that argue a BDSM relationship is fundamentally incompatible with a healthy romantic relationship, and just as many sources arguing otherwise, so Sherlock abandons his computer, clasps his hands beneath his chin, and sits for several long minutes, considering.

In the end, however, he decides that since John has already shown himself to be in favour of hurting Sherlock or being hurt by Sherlock in a sexual context, he must not find such a thing unhealthy. In fact, John has in the last few days shown numerous indications of having been involved in a BDSM relationship before—

Sherlock stops himself, halts his spinning mind mid-deduction, because the thought of John’s previous sexual relationships—and worse, of John sharing with others what he is now just beginning to share with Sherlock—is… unpleasant. Shattering. All the terror of leaping off a building but none of the joyous rush of having survived the fall.

Instead, Sherlock thinks about pain—of _sadomasochism_ , according to the internet. He owns a riding crop, needles, a hairbrush, rope, a cigarette lighter, and handcuffs. John owns an aluminium cane, scalpels, and a gun. Not to mention, they both have teeth, nails, and very capable hands.

In addition to their combined knowledge of human anatomy and John’s medical knowledge… they have everything they might need, Sherlock thinks.

*

For the next week, John examines Sherlock’s neck multiple times a day, applying arnica cream often and monitoring for strange or delayed healing.

It’s glorious. Sherlock’s throat—vulnerable, crushable—framed by John’s hands, John’s thumbs tracing the shape of each row of teeth marks.

Sherlock feels like the bat on their mantel, pinned to a board behind a thick layer of glass: appalling to most, but irresistible to the one that owns him, worthy of being displayed above the fireplace like a prized treasure.

“Hydrochloric,” he finds himself blurting during one such examination, after he’s become lost in his own labyrinthine mind, and his body, as it is unfortunately wont to do, attempts to take control.

John, kneeling on the carpet in front of Sherlock’s chair, settles back on his haunches, abandoning his scrutiny of Sherlock’s largest bite mark. “I beg your pardon?”

Sherlock breathes, forces his transport back to its proper place, although he can hardly pretend he hasn’t spoken. He’s been waiting for John to broach the subject, not wanting to seem too eager, but there’s nothing for it now, he supposes.

“My safeword,” he says. “I’ve decided on hydrochloric.”

It was the first word that popped into his head when he sat down to ponder it. Probably because he had, not two hours prior, been reading online about the sentencing of a woman in America who had submerged her unconscious husband in hydrochloric acid, killing him.

Still, regardless of his reasons for choosing it, it seems to Sherlock as good a choice as any.

“Hydrochloric,” John repeats, standing with a small grunt of exertion. He swipes at his trousers several inches above where they are actually scuffed and wrinkled from kneeling on the floor, and fondness wells up in Sherlock like blood from a fresh wound. “Seems a bit long, doesn’t it?”

Sherlock considers. He can’t recall anything from his research that indicated safewords had to be a particular length. “Four syllables. Yes, I suppose that is ‘long’ to people with a certain vocabulary size.”

“Don’t be a cock,” John says. “I was just saying.”

Then he steps forwards and, to Sherlock’s surprise, climbs into Sherlock’s lap. Each knee wedges between the chair arm and the seat cushion on either side of Sherlock’s hips, and John’s bottom rests on Sherlock’s lower thighs. Hastily, Sherlock wraps both arms around John’s waist to prevent him from falling.

He always seems so small like this. Never as heavy as Sherlock expects, and although Sherlock can—and often does—take up a similar position in John’s lap, it requires more fussing and squirming and limb shifting before they are both comfortable.

Sherlock leans back, turns his face up in anticipation of being kissed, but John does nothing of the sort.

“And your limits?” he says instead. “Given any thought to those?”

“Hard or soft limits?”

 _See?_ Sherlock thinks. _Not entirely a novice. I know the terminology._

But John seems neither impressed nor surprised. He only shrugs. “Either. Both.”

“Hmm. No hard limits.” Oddly, this causes John’s eyebrows to soar, so, giving himself no time to contemplate that, Sherlock plunges ahead. “Soft limits include”—he thinks quickly—“activities involving urine or faeces, food, animals, third parties, anything that will interfere with an experiment or a case, or anything involving humiliation, discipline, or degradation.”

By the end of Sherlock’s list, John is wearing the squinty eyes, small mouth, and creased forehead of the deeply unimpressed. Sherlock supposes he should have anticipated that. After all, humiliation and discipline seem rather commonplace in BDSM relationships, according to his research.

And although it sounds awful—being punished like a child, being made to feel lacking—if John enjoys it, if John expects it….

“By the latter,” Sherlock adds swiftly, “I of course am referring to acts that could be labelled ‘extreme’ by—”

“It’s fine,” John says, reaching out with both hands to stroke the hair on either side of Sherlock’s temples. Sherlock has the distinct and unsettling feeling that he is being soothed like a spooked horse. “Those are all hard limits for me, actually, so that works out well. Well, maybe not the food bit or the discipline, but they’re not something I particularly care about, so I’m fine with avoiding them.”

Sherlock scrutinises him. Direct eye contact, open body language, relaxed shoulders: telling the truth.

“Listen,” John says, licking his lips. His hands still just above Sherlock’s ears. “There’s no reason to jump into this right away. Why don’t we take it slowly, see what sorts of sensations you like and you don’t like before we—”

Alarm. Sherlock’s heart pounds, panic like a shrieking siren throughout his body. It’s an irrational reaction; he knows this. John has said nothing surprising, nothing worth becoming upset over. Still, the reaction persists.

 _Do not_ , he thinks wildly, _take this from me. Please._

Aloud he says, stiffly, “If you think that I am a… a _child_ that requires—”

“I think,” John answers, “that this is new to you. And you’re about to toss yourself headfirst into it, like you always do when you discover something interesting. And that’s… that’s not good, Sherlock. One of us could get overwhelmed, you could find yourself in the middle of something you don’t like with no idea how to ask for it to stop—”

Sherlock arches an eyebrow. “Can you honestly imagine that I would endure something I don’t want without complaint?”

He’s cheered when John grants him a soft smile and an even softer “No, not really. Although this is a bit different than telling a client to stop being boring. But….”

John breathes deeply, considering Sherlock silently. His hands continue stroking Sherlock’s hair, and Sherlock closes his eyes, allowing the gentle touch to sooth the rest of his lingering panic.

“Right,” John says finally. “Okay. Do you have an especially strong interest in shamming at nonconsent? One of us says no but the other is meant to ignore it, that sort of thing?”

Mentally, Sherlock dissects the idea, imagines both him and John in either role. “I wouldn’t be averse,” he decides. “But a ‘strong interest’—no.”

“Okay. In that case, let’s just say if either of us loses interest, wants to stop, gets overwhelmed, and so on, we can say ‘no’ or ‘stop’ or ‘hydrochloric’ or… or anything that isn’t ‘yes please,’ really. And we pause regularly to check in with each other. All right?”

Sherlock is being coddled, he realises. Treated precisely like the amateur that he is, the amateur that John has just accused him of being. His hackles rise, and he wants very much to fold his arms and huff and turn away in protest, but that would mean letting go of John, something he is very much loathe to do at the moment.

“Sherlock.”

John’s fingers trail along his jaw and skim down his throat, skipping over the bite marks entirely—Sherlock has a mental map of them so detailed it could rival his mental map of London—but still, no doubt inadvertently, reminding Sherlock of them. The sharp pain, the feeling of being John’s, John’s unflagging erection pressing against him, John calling him “sweetheart.”

 _Cooperate_ , he thinks. _Cooperate, and you can have it again._

“All right,” he answers. He arches slightly, letting his eyelids droop and his lips pucker, making himself appear as sensual and tempting as possible: a decent facsimile of the naked women on John’s computer. “Bite me again?”

With a smile, John bends forwards and—ah, yes—kisses him. Softly, though: barely a brush of his lips against Sherlock’s.

“Maybe later,” John says, and kisses his forehead, then the top of his head. “Feeling a bit peckish, actually. I might make a sandwich. Do you want one?”

Sherlock doesn’t, and spends the rest of the afternoon sulking pointedly, although John still doesn’t offer to hurt him again.

*

The healing of the largest bite has, according to John, become somewhat delayed, possibly owing to—again, according to John—Sherlock’s “fucking awful diet,” so John insists on buying Sherlock a bottle of multivitamins and then ensuring that Sherlock takes one a day.

(Sherlock accompanies John to the chemist’s to purchase them, and no less than seven people stare at his bared, bitten throat, either blatantly or subtly. Satisfaction coils like a lazy snake in Sherlock’s gut, and he walks tall and straight and swishes his coat dramatically when he turns and feels bloody _fantastic_.)

An hour after Sherlock takes his first multivitamin, he sits down at the kitchen table with the rest of the bottle, intent on scraping the coating from one of the pills and then crushing it and examining its composition.

He’s only managed to scrape off half the coating using a scalpel, when he hears John enter the kitchen and stop just behind him.

“How do you feel about scratching?”

Sherlock pauses his scraping to consider. “About the same as any other piece of evidence, really. Scratches are sometimes significant, sometimes irrelevant. I once investigated the murder of a man with a tendency to self-scratch in times of stress. Scotland Yard mistakenly believed his self-inflicted scratches were—”

“No, not—” John laughs. The sort of laugh that means Sherlock has done something unintentionally amusing, but Sherlock never feels laughed at. He feels warm, proud of having contributed to John’s happiness even without meaning to. “Not what I meant.”

John is still grinning as he edges around the table and sits across from Sherlock, clasping his hands in front of himself. The pose reminds Sherlock distinctly of the one John adopted when asking Sherlock to be his best man. It’s a pleasant memory; the words “best friend” in John’s voice, referring to Sherlock, still ring like a wind chime in Sherlock’s mind palace from time to time.

“I meant,” John says, “scratching as a sexual activity. Like what you did to my back, but intentionally—and somewhere on you. How do you feel about that?”

Sherlock doesn’t even need to consider it. “Acceptable.”

It’s more than acceptable, in fact. It’s exquisite. If John can be convinced to scratch hard enough, perhaps deeply enough to draw blood…. Sherlock’s blood under John’s nails. The healing wounds cracking open the following day, staining Sherlock’s shirt. Sherlock moving stiffly, being asked if he’s all right, complete strangers noticing his discomfort—

He’s becoming aroused at just the thought.

“Sherlock?”

Sherlock shakes away his stupor and stands, nearly knocking over his chair in his enthusiasm. “You’ll want to continue in the bedroom, I assume?”

To Sherlock’s surprise, John’s eyes widen slightly. “Erm, no. I thought we’d just stay out here while we discussed it, but—”

“Discuss it? What for? I’ve already said it’s acceptable. We can proceed directly to the scratching.”

“No,” John says. “We haven’t talked about where I’m going to scratch you, how I’m going to scratch you, what we’re going to do before and after….”

Sherlock rather wants to snap something in response, something that will hopefully communicate how very much he does not care where or how or what, just as long as John is the one to do it.

But John said _‘I want a healthy relationship_ , _’_ and Sherlock has embossed those words, framed them, and nailed them to every wall of his mind palace so he will not forget them.

And, according to his research, negotiation is part of a healthy BDSM relationship.

So Sherlock swallows his impatience and his desire, and lowers himself back to his seat to negotiate.

*

He is forced to wait nearly two full days to be scratched.

Because John has work—John has to be asleep at a certain time, be awake at a certain time, and apparently the ten or twenty, perhaps thirty if he intends to draw it out, minutes it would take to scratch Sherlock and then get them both off does not fit into this schedule.

John expects him to “drop,” Sherlock knows. Which means he intends to provide Sherlock with extensive “aftercare,” and the promise of further “sweetheart”s and “love”s and coddling convinces Sherlock to be patient.

And oh, his patience is rewarded.

Just as they discussed, he is laid prostrate in the centre of the bed, and John climbs atop him, straddling his bottom, and scratches.

The first few are gentle, tentative, involving more fingertip than nail, trailing up and down either side of Sherlock’s spine so lightly it begins to tickle. He shivers and squirms and snaps, “Harder, for god’s sake—”

Immediately, John’s fingers curve, and he drags his nails in a swift swipe from Sherlock’s shoulder to the bottom of his ribcage.

It stings. Not excruciatingly, not even really unpleasantly, but just enough for Sherlock’s receptors to identify the sensation as a sting rather than a brush. His breath catches, and he pictures his skin growing pink and blotchy while John watches.

“Harder,” he says. Then, because he can sense John hesitating, he turns his head to the side and says, “Yes please, green light, whatever I need to say to make you do it again but _harder_.”

“Shush,” says John. There’s a smile in his voice. “Let me take it slow. I want to see all the different marks I can make on your skin.”

 _Oh_. Sherlock turns his head back with a moan, closing his eyes and revelling in the thought of John not simply marking him but _enjoying_ it, of John enjoying it so much he wants to experiment, of John—of John—

The pain builds, until finally it begins to feel his back is on fire. Like a carmine stain, everything becomes red-tinged and sharp. He’s aware of every wrinkle on the duvet beneath him, every millimetre of skin John touches, every time John’s nails slip and skid, every pained little cry that comes from his own mouth and how each one makes John’s hips twitch and his breathing stutter.

“All right?” John asks every two scratches, or “Too much?” or “Still with me?” And then, every time Sherlock indicates that yes he’s fine and please continue: “My perfect boy. You’re doing so well, Sherlock.”

It lights Sherlock up like a spill of petrol, burns him quickly dry.

Sherlock is perfect. Sherlock is John’s.

The pain falls away, insignificant. Sherlock floats. A ship on the calm midmorning sea, water lapping gently at the hull.

“All right,” John says suddenly, and Sherlock realises with an unpleasant jolt he’s no longer being scratched. “That’s enough, I think.”

 _It’s not_ , Sherlock thinks dimly. _It will never be enough. Why do you always see but never observe?_

But he says nothing, allowing John to climb off and curl up beside him on the bed, close enough that it could conceivably be called a cuddle. John’s chest is pressed against his arm, John’s chin against his shoulder, John’s erection against—

 _Ah._ Sherlock blinks, rousing himself even further from whatever headspace he’s fallen into. John is erect.

Sherlock is not. Has not been for… well, he isn’t sure how long. Since at some point when he was being scratched, presumably.

Is that a problem? It must be. Surely John would prefer him to be hard and wanting, is even now wondering why he isn’t. After all, they both got off after the biting last time. John must expect the same now.

“Hey,” John says, shimmying closer and nuzzling Sherlock’s shoulder, kissing just above the bone. “Are you okay?”

“Of course,” Sherlock answers.

He has no reason to not be okay. He isn’t erect, obviously, but that can be remedied.

Sherlock rolls to face John, clamping down on the urge to hiss and flinch when the movement irritates the fresh scratches on his back. He thinks determinedly of his cock in John’s arse, how John goes utterly silent when Sherlock fucks him, just stares into Sherlock’s face with the same expression he wore during their very first case, all those years ago, like Sherlock was doing something rare and awe-inspiring when Sherlock was merely being his ridiculous, arrogant self.

When Sherlock’s cock finally begins to thicken, he reaches for John, does his best to look lust-fogged and desperate even as concern scrawls its thick lines across John’s face.

“Hey,” John says. “Hey, shh, it’s okay—”

“Please, John,” Sherlock tells him, and squirms even closer still, plastering them both together. “I need it, _please_.”

He begs with his entire body, winding his arms around John and dragging his fingertips through John’s hair, kissing the thin, tense line of John’s lips and shoving his prick—not quite half-erect, but getting closer, oh, much closer—against John’s thicker, harder one.

And John, agreeable and easily swayed, is reciprocating in a matter of seconds. Suckling Sherlock’s bottom lip and cupping Sherlock’s cheek in one palm with such tenderness that Sherlock feels weak and boneless in the face of it.

“Touch me,” he pleads, and it’s only partly affectation now. He wants it: the irresistible burn of orgasm, the stink of John’s ejaculate on his skin. “For god’s sake, John, please touch me.”

John obliges and grips Sherlock’s cock with both hands and strokes him expertly, effortlessly, to full hardness. Pumping the shaft tightly but slowly until Sherlock feels as though he’s being wrung like a soiled, sopping-wet shirt. He jerks and sobs, moving with John, trying in vain to fuck John’s fists as much as he’s being fucked by them.

Throughout it, the skin of his back throbs ceaselessly, the pain of it vying with the pleasure of John’s hands for his attention. He wonders vaguely if maybe John broke skin after all, if the scratches are even more puffed-up and red than the ones on John’s back were. He hopes so. Oh, he hopes so.

Just the thought of it makes him dizzy and shivery. Makes him want to still his hips and stop John’s hands and simply lie against John’s chest, listening to John’s heart churn like the perfect machine it is and savouring the scratches’ sting like a nicotine addict puffing the last dredges of his last cigarette—

 _No_ , he tells himself. _For once in your life, do not be selfish_.

His orgasm is… somewhere, he thinks. Not far, but not here. Just a bit closer, a bit more.

“I need to come,” he says, and can’t help but screw up his face, hoping John mistakes it for an expression of desperation instead of the frustration it is. “Oh god, let me come. Please.”

“It’s okay,” John tells him, and draws him close with one hand, bringing Sherlock’s forehead to his clavicle and kissing the top of Sherlock’s head sweetly, while the other hand carries on, moving faster now that it’s alone on Sherlock’s prick. “Just relax and let it happen. You’re okay, love.”

 _Love._ That word again. It’s Christmas, that word. It echoes like a church bell in his mind until finally, _finally_ , his body gives in.

“There we go,” John murmurs, gentling his strokes as Sherlock begins to come. “That’s it, sweetheart. You gorgeous thing. My perfect Sherlock.”

 _Yes_ , Sherlock thinks dimly. _I’ll do anything. Please._

*

“No blood,” John declares much later, after he’s led Sherlock into the bathroom so he can examine the scratches in better light. “Didn’t think so, but I wanted to make sure.”

Sherlock is too sated to be disappointed. He stinks of sweat and semen, and he can see in the mirror that his back is a sprawl of raised red lines. The lack of blood seems inconsequential. John has still no doubt scraped off countless skin cells, and John doesn’t clean his fingernails as meticulously as Sherlock. Sherlock’s skin cells will remain trapped beneath them for days.

“Are you all right?” John asks.

There is so much affection, so much _devotion_ , in John’s tone; it coils around Sherlock’s throat and squeezes, robbing him of any response aside from a nod and a nuzzle.

John is so much shorter that Sherlock has to bend considerably to nose at his neck. It stretches the skin of his back, makes the scratches pulse with pain.

 _I am yours_ , he thinks, nuzzling harder as John’s fingers rake tenderly through his hair. _It might as well be written in my DNA. If you leave, it will invalidate my entire genetic material._

“I want to be hit,” Sherlock says. Bruised deep. Capillaries broken. “And cut.” Open wound. Blood. _Scars_. “Oh, god, I want to be cut.”

“Shh,” John says. “For now, let’s just have a bath so I can clean your back. We’ll talk more later, all right?”


	3. Three

By the time Sherlock is summoned to another crime scene, the scratches on his back have healed and been replaced with a fresh set, at his own urging. He also has a new assortment of bite marks and bruises on his neck, again at his own insistence.

That morning, Mrs Hudson catches sight of the latter while John is in the shower and shakes her head, clucking her tongue as though in disapproval.

“Goodness,” she says. “Possessive one, is he? Although… you know, I suppose he does seem the type.”

Sherlock, seated at the kitchen table with his microscope and several crushed multivitamins, drops his head back with a grin so Mrs Hudson can see the full collection. They’re glorious, he knows: mottled blue and violet and brown. He looks at them often, and spends even more time running his fingers over them, poking at the marks until they ache.

Mrs Hudson’s mask of disapproval cracks, and the corner of her mouth twitches upwards. She bends close, patting his shoulder gently, and whispers, “Good for you, dear!”

Yes. Very good for Sherlock. He hasn’t yet managed an erection that doesn’t flag when John hurts him, but that’ll come eventually, he’s sure. As usual, his body is lagging several steps behind his mind.

His good mood lingers for the rest of the morning, and when Lestrade rings in the early afternoon with a badly mutilated body discovered in an abandoned car in a car park, Sherlock feels almost giddy at the opportunity to show off—properly, this time.

So when he leaves the flat with John in tow, he ensures his scarf is left behind, and when they arrive at the crime scene, he ensures his coat collar is turned down for once, his throat bared.

He and John are met at the edge of the blocked-off car park first by Donovan, who scarcely glances at them as they duck under the police tape. She leads them through the small crowd of officers and underlings milling about.

“I’ll warn you,” she says over her shoulder, “this one’s a bit of a shocker. It’s hard to turn my stomach anymore, but… well.”

“Yes,” Sherlock says, feeling suddenly quite waspish, “thank you for the warning, although I’m sure we can handle it.”

He shoves past her, his head high and his neck straight, but Donovan isn’t even looking at him. Isn’t really looking at anything, in fact. Her nails are uncharacteristically bitten; her skin appears clammy. She’s shaken. By the “shocker,” he supposes and promptly gives her up for the moment as a lost cause.

No matter. It’s hardly her opinion Sherlock is concerned with.

He finds Lestrade a short distance away, standing with his hands on his hips and a hunted expression on his face. Sherlock strides towards him, and when Lestrade spots him, he blinks and—ah, yes, _finally—_ his gaze fixes almost immediately on Sherlock’s throat.

Sherlock can see the moment Lestrade realises what he is looking at. His eyes widen the slightest bit, and the slow, rusted gears in his mind practically screech as they begin to turn.

Sherlock feels incandescent. Bitten and bruised, marked, with John standing just behind him, wearing Sherlock’s deodorant, strands of Sherlock’s hair clinging to his coat. Their intimate relationship is as obvious as the sun in the sky and the strong scent of death in the air.

Then Lestrade clears his throat and steps forwards, ducking his head so he can ask in an undertone, “Just for my own peace of mind… all consensual, yeah?”

A trickle of pleasure down his spine. Finally, someone else to acknowledge the most momentous occasion of Sherlock’s otherwise dismal life.

“Of course,” Sherlock answers. Then he waits for the inevitable question that will follow. The “Who?” or, if Lestrade has been more observant than Sherlock has given him credit for, “John?”

But Lestrade only nods once and steps back, lifting his head again. “Right. Well, you’re gonna need full protective gear for this one. It’s a mess, and unfortunately this time I can’t risk you contaminating the scene just to keep you cooperative.”

Sherlock blinks, taken aback and… disappointed? Why is he disappointed? Because he hasn’t yet got the chance to say that John is his… something?

He still doesn’t know what label John prefers, he realises.

“That’s fine,” John says, stepping around Sherlock, who is standing frozen like a marionette without its strings. “Protective gear is… fine, isn’t it, Sherlock?”

“Apparently,” says Sherlock, and that is, apparently, that.

*

It niggles at him, long after the case is solved—disgruntled former employee, tediously easy to solve once Sherlock has all the facts—although he knows there is no reason for it.

Lestrade clearly understands that Sherlock is involved in a sexual relationship. Why should it matter that Sherlock wasn’t given the opportunity to explicitly identify John as his sexual partner? It shouldn’t. Of course it shouldn’t.

It does.

“What’s the matter?” John says. His impossibly slow hunt-and-peck typing halts, and Sherlock realises that he is staring at John and has been for an indeterminate amount of time. “You look… upset.”

He sounds baffled, because of course Sherlock has no reason to be upset. He’s just solved one case, his inbox is slowly filling with potential future cases, and John is less than two metres away and _his_ as Sherlock has always wanted him to be. Why should Sherlock be anything other than perfectly content?

With a heavy sigh, Sherlock flops onto his other side, curling into foetal position with his nose to the back of the sofa.

He waits for John’s answering sigh. For John to return to his computer, to typing up his notes on the case and constructing his usual appallingly punctuated and overly dramatic blog post that will describe their “adventure” in great detail, describe _Sherlock_ in great detail, but say nothing about what Sherlock is to him. He will give no indication in his writing that one week ago he crouched over Sherlock and raked his nails down Sherlock’s back like a plough through soil and then, at Sherlock’s urging, knelt between Sherlock’s open thighs and masturbated while Sherlock kept his own arse cheeks spread, so John could see his tight little hole (could think of that instead of Sherlock’s hatefully limp cock) and get it nice and wet with semen when he came, Sherlock’s name on his lips.

But John doesn’t take up his typing again. Instead, his sigh is followed by the sound of his laptop clicking shut, then his chair skidding across the floor and creaking as he stands and moves away from the desk.

“Hey.” The cushion shifts as John grips the edge of it, using it to keep himself steady as he kneels on the floor in front of the sofa. “All right, love?”

John must know, Sherlock thinks with a shiver, he must know how that word affects him. A violin string snapped mid-note, a bullet halted by brick, Sherlock can’t ignore it, can’t focus on anything but it.

But John isn’t manipulative like Sherlock. He doesn’t do things just to gain a response. He is honest and good. He is genuine.

Sherlock rolls to his back, peering up at John who gives him a smile darkened by concern. He thinks that Sherlock is on the verge of a black mood, that he’s being ravaged by post-case boredom. Better than the truth, Sherlock supposes.

He lifts himself to his forearms and scoots backwards, propping himself up against the arm of the sofa before he reaches for John, who comes easily. Sits between Sherlock’s bent knees and lifts both Sherlock’s hands so he can kiss each knuckle. Ever obliging, ever affectionate.

John Watson is a well of affection, and Sherlock worries often that he is going to drink him dry.

They are too old, too grown, to spend hours snogging on the sofa, particularly a sofa this small, but nevertheless, Sherlock adores doing so. How one of them has to climb atop the other, wind around each other like wires, to prevent one or both from falling off. How Sherlock is free to relish John’s weight on him, John’s hands on either side of his throat, John’s mouth on his, and imagine that there is nothing biologically impossible (or _unhealthy_ ) about wishing he could somehow saw his own sternum in two, pry his ribs apart, and take John into himself, keep him there with his other most crucial and invaluable organs for the rest of time.

When John pulls away, Sherlock almost feels John’s taken his heart, lungs, and even bits of his liver with him, but he stays where he is. Admires how John’s eyes are dilated with arousal, how his mouth looks wet and swollen, while he waits for John to come back.

“Would you mind,” John says, “marking me up a bit this time? I know we usually do it the other way round, but I thought… um.”

Would Sherlock _mind_? Sherlock has killed for John, has laid his metaphorical heart at John’s feet. There is very little, he thinks, he would not do for John Watson.

“Where?” says Sherlock, hoping he doesn’t sound too eager. “How?”

“Erm.”

John moves even farther away—Sherlock’s fingers twitch, aching to retrieve him—and clumsily yanks his jumper over his head, followed by the t-shirt he’s wearing beneath, and tosses them both aside. His torso is bared; his scar is bared. Sherlock hasn’t worshipped that scar in days, he realises. He should rectify that immediately.

“Around here, I think.” John rubs at the join between his neck and his right shoulder, then makes an arc across the top of his chest to rub at the same spot on his left side. “Easier to hide. You might like to show yours off, but some of my patients wouldn’t be too keen on their GP showing up to work with a mess of hickeys.”

_Pity_ , Sherlock thinks, but doesn’t dwell on it.

Instead, he draws John back down so he can reach the bit of skin John indicated. He presses his lips gently to it.

“Here?”

“Yeah. But no teeth. Just, you know… suction.”

_Suction_. Sherlock closes his lips experimentally around a sliver of skin and sucks.

John sighs pleasantly, and his hands find Sherlock’s hair as he angles forwards, putting even more of his weight on Sherlock’s chest. “Mmm. Little harder.”

Sherlock complies and is rewarded with a soft moan, John arching into his mouth.

“Good. That—oh, mmm… a little too hard now, actually.”

Sherlock stops immediately and leans back, licking his lips as he surveys the small pinkened patch his mouth has left behind. To his surprise, there are vague indentations of teeth around it, although he recalls very specifically leaving his teeth out of it—a little disconcerting, that, but John thankfully either didn’t notice or doesn’t mind.

“Again?” John asks, already presenting his neck again, and Sherlock doesn’t hesitate to oblige.

The bruises bloom slowly on John’s skin. When Sherlock switches to John’s other side, he leaves behind two bright pink mouth-shaped blotches, and when he returns, he finds both have darkened to a deep red. He kisses them both, laves them gently, worships them much like he worships John’s scar, and when he pulls back again, one seems to have gained an almost purplish tinge.

He aches at the sight.

By then, Sherlock is nearly flat on his back on the sofa with John on top of him, looking down at him. Marked, wearing the shadows of Sherlock’s mouth, wet with Sherlock’s saliva, and so aroused that Sherlock can smell it.

Sherlock needs to be hurt. Right now—John’s mouth at the joins of his own neck and shoulders, giving Sherlock a matching set of bruises. He wants to wear this moment on his own skin the way John is wearing it on his: beautiful and brutal.

And afterwards: John’s tender stroking hands, John allowing Sherlock to nuzzle senselessly at his scar, John’s voice murmuring “That’s it, sweetheart” in his ear.

“Oh my god,” John says, breath expelling in a rush. He sounds awed, lost. “I am so turned-on right now.”

Of course he is. John’s arousal is evident in not only his smell but his eyes, his breathing, his temperature, and of course the hard cock tenting his trousers, pressing into Sherlock’s stomach.

If Sherlock asks to be hurt, the moment will be ruined. John will feel compelled to ignore his own erection, until after Sherlock’s been dealt with and then sufficiently coddled and looked after and re-aroused after his body fails him. Selfish—he will not be selfish.

It’s not even a hardship to toss aside his own desires, to wrap his arms around John’s waist and trail his fingers down John’s lumbar curve and into his trousers, to grope John’s arse and relish John’s groan and the involuntary thrust of John’s hips.

Sherlock adores him. To lose John now, after all this… it would wreck him.

“Which would you prefer?” Sherlock murmurs. “My mouth, my hand, my arse, my cock—”

“Your hand,” says John, wriggling against him, already beginning to pant. “Christ, your hand, but… I want to come into your mouth. Is that all right?”

“Of course,” Sherlock assures him, already moving: tipping John onto his back so Sherlock can crawl between his legs and open his zip. “Anything you want.”

*

That night, John lies on his side in bed, and Sherlock curls up behind him, his head resting between John’s shoulder blades and his knees slotted perfectly against the backs of John’s.

He’s meant to be allowing John to sleep undisturbed. John has a shift at the surgery the following morning, and _tetchy_ doesn’t even begin to describe John when he’s not had a sufficient amount of sleep.

But John is deliciously sex-drowsy and rumpled, still smelling faintly of ejaculate, and has opted to sleep shirtless (although unfortunately not pantsless). Sherlock’s soil samples, waiting in the kitchen, pale in comparison to the opportunity to savour the sight, scent, and feel of John Watson in his bed.

Besides, for the moment at least, John seems content to allow Sherlock to remain plastered against his back. He stays hovering at the cusp of stage one sleep, snuffling and twitching a bit if Sherlock breathes particularly deeply or tries to shift position, but never waking fully.

When John finally slips into stage two, he stops responding to Sherlock’s presence at all. It implies a deep trust in Sherlock that is almost devastating, given John’s proven trust issues. Sherlock will almost certainly never be worthy of that trust.

He noses gently between John’s scapulae, testing his response, and when he doesn’t react at all to the touch, Sherlock allows himself to indulge.

He trails his hands over John’s scar, admiring its weblike texture, tastes the sweat dried at John’s nape. Then he spends several minutes tracing an anatomical heart on John’s skin with a fingertip—larger than John’s actual heart and not positioned even remotely correctly, but it hardly matters. It soothes something in him to do it, and to be able to see in the dim light from the hallway how John’s skin dips beneath the weight of his finger, so he can almost believe he is leaving something behind more significant than dead skin cells, oil, and bacteria.

Ridiculous, he knows. The heart isn’t even the source of sentiment as popular culture pretends it is. There’s no reason for him to fixate on it. So he traces the lungs as well, then the kidneys and liver, wondering as he does so what John’s look like—how their size and colour and surface texture compare to the average forty-four-year-old male’s.

_I have_ , Sherlock thinks wistfully, _seen the organs of countless cadavers, but I will never see yours. Pity._

Not a good thought, he knows. Not strictly _healthy_ , perhaps. No matter Mary’s deficiencies as a romantic partner, even she probably never wanted the things that Sherlock wants.

He traces organs with his fingertip until his eyelids begin to droop, and then he finds himself thinking muzzily of John cutting him open and carving _John H Watson_ along the inner curve of each of Sherlock’s ribs.

Eventually he falls asleep, spooned against John’s back.

*

John’s blog post, when it is finally finished, is every bit as dramatic and poorly punctuated as Sherlock anticipated.

And also every bit as devoid of romantic (or sexual) sentiment.

It makes sense, he supposes. John values his privacy. John strays from anything too personal or sensitive in his blog. Sherlock hardly expects a long-winded emotional outpouring or pornographic musings.

Although, he thinks, a simple _mention_ wouldn’t be remiss, given the value John puts on honesty and how he prides himself on being a trustworthy source of information.

Sherlock considers leaving a comment. Something flirtatious, perhaps, something pertaining to the four love bites Sherlock left on John’s skin or how unfortunate it is that Sherlock’s own are fading or whether John has any interest in finding out if, for instance, Sherlock’s arse bruises as well as his neck.

_Hmm_ , he thinks.

“What are your thoughts on spanking?” he asks aloud.

“I beg your pardon?”

Not John’s voice. Sherlock glances hastily up and is taken aback to find John nowhere in sight and Mrs Hudson carrying a tray of tea towards him. Her expression is cheerful as she sets the tray on the desk beside his computer, no indication that she’s bothered by the subject of his inquiry at all.

“Where’s John?” he says.

“At work. Dr Roucayrol is out with flu, apparently, so John’s filling in. He said you probably wouldn’t remember, but he told you about it this morning.”

Ah. That explains the tea, then. Mrs Hudson only ever brings up tea anymore when John’s asked her to because he’ll be gone.

Sherlock despises when John is gone. That he insists on maintaining a job aside from simply being Sherlock’s partner and blogger is positively hateful.

“I’m so glad you two have worked everything out,” Mrs Hudson says. Once the tea tray’s been sorted, she seats herself in John’s chair, smoothing her skirt beneath her.

Sherlock must seem especially lonely without John today, he supposes. “‘Worked everything out’?”

“Mm. I always thought there was something between you two, you know. From the moment I saw him, I knew he’d be good for you. But then there was Mary and the wedding….”

Mrs Hudson’s lips tighten and thin like a piano wire, and the look she gives Sherlock is sopping with pity. Unnecessary, of course. Sherlock was perfectly content—thrilled, really—to be the best man, the best friend.

After a second or two of silence, Mrs Hudson says, “After I saw the two of you dancing, I thought there mightn’t _be_ a wedding, you know. At least not one with Mary. The way he looked at you….”

Sherlock remembers. John’s eyes were bright, his features softened. He giggled a lot, stared up at Sherlock like he was squinting into the sun. Sherlock didn’t allow himself to collect much data beyond that; he knew he would misconstrue it, let sentiment bias his observations.

Mrs Hudson carries on talking, something about “relieved that’s all sorted” and “glad you’re finally happy,” but Sherlock ignores her in favour of recalling the details of John’s wedding. Standing beside John for pictures, sitting next to John at the reception, playing his waltz for John.

_‘At least not one with Mary,’_ Mrs Hudson said. Would John have any interest in marrying him?

Unlikely. Sherlock cannot fathom a world in which anyone, even John Watson, would consider him ideal for marriage. Not to mention, after having endured one previous failed marriage, John will no doubt be more cautious of entering into any future marriages.

Still, it’s not an unpleasant thought: putting himself in Mary’s position. He wonders if being a groom would exclude him from being the best man. He rather likes the idea of being both, of being John’s best friend and husband.

And obviously he would compose a new waltz for the occasion, although there would have to be a recording of it played at the reception if Sherlock is to be the one dancing with John. Then perhaps he could play it live for John later, when they are alone, while John watches him like the sight of Sherlock playing for him is a treasure worth more than the ring on his finger….

By the time that Sherlock tires of the fantasy, Mrs Hudson is gone and his tea is cold.

*

Sherlock returns to his research on BDSM relationships, but this time he narrows his focus to strictly the S and M bits. After all, John’s shown no interest in bondage or domination, and after careful consideration, Sherlock decides that his own interest in either is minimal.

So: sadomasochism. Which, as the name implies, must involve both a sadist and a masochist.

John is a sadist, obviously. He is undeniably sexually aroused by the act of inflicting pain on Sherlock. (And at that thought, Sherlock loses himself for several long minutes picturing John’s hard cock, the sight of it straining against John’s trousers, the feel of it hot against Sherlock’s skin even through the layers of fabric.)

And perhaps John is a bit of a masochist as well… or perhaps not. He wanted to be marked but not bitten. (Another several minutes are lost recalling how John bared his throat to Sherlock like a conquered, submissive animal, so earnest and trusting, so small and alive although his capillaries were breaking as he arched eagerly into Sherlock’s mouth.) Is suction painful on its own? Sherlock assumes it is significantly less so, but admittedly has no frame of reference. He’s only asked to be—and thus only been—bitten.

As for Sherlock’s orientation, however… that requires a bit of breaking down facts before he can pin it down.

Fact: Masochism (noun) is defined as “sexual enjoyment from being hurt or punished.”

Fact: Sherlock has not once managed to sustain an erection (traditionally considered the most reliable indicator of sexual enjoyment and desire to engage in sexual activity) while being hurt.

Conclusion: Sherlock is not a masochist.

Not good. If John is primarily a sadist, and sadomasochism requires both a sadist and masochist, it suggests incompatibility—the inevitable development of disappointment.

Not to mention, John quite clearly said the he didn’t mind a little pain _‘during sex.’_ Can the context of the encounter still be considered sexual if one participant is not aroused? Seems unlikely—in the same way that it isn’t a murder if the victim hasn’t died.

Particularly true from John’s perspective—John who values equality and consideration. In fact, Sherlock suspects John would find the very idea—one person purposefully injuring another person, becoming aroused and getting off while the injured party is not and does not—offensive. Unhealthy.

And what does it say about Sherlock, he wonders, if he enjoys being hurt— _craves_ it—even if his body apparently doesn’t find it arousing?

Very not good.

Sherlock shoves the computer aside and steeples his fingers beneath his chin, closes his eyes, and considers.

Fact: Sherlock’s transport often refuses to do his mind’s bidding. (See: any number of tedious biological necessities, physiological responses to irrational emotion, etc.)

Fact: In the past Sherlock has, after many repeated attempts, succeeded in retraining his transport to respond appropriately to certain stimuli. (See: hunger, sources of minor discomfort during cases, etc.)

Conclusion: Sherlock need only persist in what he has been doing to overcome this. His transport will learn, eventually.

_And John won’t grow disappointed_ , Sherlock reassures himself. _He’ll make your entire anatomy sing with pain and sob with pleasure, and he’ll call you his sweetheart while he glides his cock inside you and fucks you so perfectly—torturously, brutally—you’ll wear the evidence of it for weeks._

In short, it will be fine. It will all be fine.

*

It turns out that John is in fact interested in spanking, although he is insistent about beginning with only bare hands rather than implements like a paddle or a crop.

“If you like it bare-handed,” he says when Sherlock attempts to argue, “we can talk about trying something else next time.”

Acceptable, Sherlock decides, and spends a great deal of time coaxing John into the bedroom so he can undress them both, position John at the edge of the bed, and then lie flat on his stomach in John’s lap.

It’s surprisingly comfortable like that: his head pillowed on his folded arms and his pelvis against John’s thighs. He sways his hips a bit, hoping the motion is suitably enticing, then shivers when John responds by dropping a hand on his arse, making idle figure-eights on the left cheek. The touch is featherlight, teasing, and it tickles.

“All right?” John asks. His voice is as soft as his touch. Perhaps even more so.

“Of course.”

Why should Sherlock be anything but? He’s endured far worse than a few smacks to his bottom, and a statistically significant portion of humanity reports enjoying sexual spanking. Whereas Sherlock has never heard of someone enjoying, for instance, a close-range gunshot to the chest.

So he is fine. Of course he is.

“All right,” John says, still stroking Sherlock’s bum. “To get you warmed up, I’m going to start slow, alternate cheeks, and check in after each one. If you don’t like something or it doesn’t feel right, tell me _immediately_ , yeah?”

They’ve gone over this. The same words, even the same inflection. But Sherlock allows himself to be coddled, to be treated like a fragile teacup in danger of shattering, because to argue would be counterproductive. John would argue back and Sherlock would grow impatient and stroppy, and it would prolong the moment when John finally gives in and spanks him properly.

“Sherlock?”

“Yes,” Sherlock sighs. “I’ll tell you.” _Get on with it_ , he doesn’t say, but he thinks it quite emphatically.

“Okay. First one. Left side.”

John’s hand lifts off his arse.

Sherlock braces himself, prepares for a starburst of pain on his left arse cheek, but it’s the sound—the _slap_ of John’s palm against his bottom seems oddly thunderous in the otherwise silent room—that makes him flinch and suck in a startled breath. The blow is barely a tap; the sensation hardly even registers in Sherlock’s mind.

John’s hand pauses, his fingers stroking over Sherlock’s skin as though there’s any pain there to be soothed. “Okay?”

Sherlock swallows, and that too—the noise of his throat working—seems unnaturally loud. “Fine. Another.”

Humming agreeably, John transfers his hand to Sherlock’s right cheek, massaging the flesh in a way that makes Sherlock want to wriggle and arch up into the touch. He’s hard, he realises suddenly. Well, a bit hard… not entirely soft, anyway. He isn’t nearly as erect as John, whose cock is nestled against Sherlock’s lower abdomen, but still, it bodes well. Perhaps his transport is learning already. Surely, with a little effort, he’ll be able to keep himself aroused during the entire proceedings.

“Second one, then,” John says. “Right side.”

The sound doesn’t seem nearly as loud now that Sherlock is expecting it, but the swat feels the same: light, almost farcically painless. Sherlock squirms impatiently as John’s fingers circle soothingly over the utterly unharmed skin.

“Still okay?”

Sherlock can’t help but snap, “ _Obviously_. You’ve barely touched me. I realise you aren’t the picture of brawn, but surely you can manage something with a bit more force.”

He expects a waspish response, perhaps even outright anger. (And oh, wouldn’t that be a treat. John in anger is glorious. His fists tight like nooses, his spine straight as a crowbar. He is steel in a cable-knit jumper, a land mine in a sleepy field. For John to take his anger out on Sherlock, to hold Sherlock down and wallop his arse with the force of a bullet racing down a gun barrel, would be— _oh_ , magnificent. He would be recovering for months.)

Instead, John sounds amused when he answers, “I told you: I’m warming you up. Have you ever been spanked before?”

Of course he hasn’t. Mummy would’ve turned absolutely monstrous if someone had struck him as a child, and he’s never taken a recreational interest until now, until John. Sherlock shakes his head, scowling down at the duvet.

“Well, I have. And believe me, Sherlock, you don’t want—”

John’s words strike with the intensity of a needle plunged into Sherlock’s vein. Sherlock stops listening, loses awareness of his senses entirely. His mind begins to reel.

_Who?_ he thinks. _How many people have had you like that, and when? Did you enjoy it? You did, of course you did, obvious, but not like this. Not bent over someone’s lap, you didn’t like that; it made you feel small, childlike. But bent over something else—table, chair, some piece of furniture specifically designed for that purpose. Oh, John._

For John to trust someone so much…. Sherlock can imagine nothing he wouldn’t do for the pleasure of that.

“—ll see,” John is saying, when Sherlock makes an effort to listen again. “For now, how about… hm, ten swats with ten seconds between each one? We could try the same location for all ten, although it might be better to alternate instead so th—”

“No,” Sherlock insists. Greater chance of leaving marks if he’s struck on the same bit of skin again and again, even if John continues to hit him lightly. “Ten in the same location is… good.”

With a thoughtful sound, John grips Sherlock’s hip and shifts him until he’s no longer lying flat across John’s lap, but with his knees bent slightly, his arse just barely upturned.

It feels considerably more whorish this way, like he is nothing but a toy for John’s enjoyment, and surprisingly, the sensation is far from unpleasant. Sherlock fights the urge to whimper, and buries his face in his forearms.

“Right, then,” says John. “Back to the left cheek, I think. Ready?”

Sherlock is, and John raises his hand.

The first few are more of the same: light, more noise than pain. John’s mental timekeeping is off, so ten seconds becomes somewhere between 11.1 and 11.9 seconds. During which he smooths his palm gently along the skin he’s just spanked, making little circling motions with his fingers, before he lifts his hand and swats Sherlock softly again.

By the seventh, however, the swats have begun to smart a bit, and by the tenth Sherlock is certain that his arse cheek is at least a pale pink.

“There we go. Ten,” John says, as though Sherlock hasn’t been counting the strikes himself.

John brings his hands to either side of Sherlock’s hips, framing his arse and then squeezing, plumping his cheeks. Something in the sight must be appealing, Sherlock assumes, and he tries to shove his bottom up even more, making his arse look as lovely and plump as John wants. He can feel John’s approval: a warm current humming through him.

“By the way,” John says, “you still remember your safeword, yeah?”

Sherlock is still being coddled, apparently. Still treated like fine china as though John honestly believes eleven total blows to one arse cheek is enough to make him forget a single word. He clenches his jaw in distaste, but still answers obediently, “Hydrochloric.”

“Mmhm. Good boy.”

One of John’s hands trails up Sherlock’s spine and combs through his hair, fingertips dragging along his scalp, turning Sherlock into a strip of magnesium over a Bunsen burner: luminous, white-hot. Slack-jawed, inexplicably panting, he lifts his head, pushing into John’s hand, inviting him to carry on scratching and petting, sure that he’ll crumble if John stops, oxidised and ruined.

“Shall we try another ten?” John asks, still stroking. “Right side this time?”

Sherlock nods, biting his lip. “And harder.”

“Maybe. We’ll see.”

The hand in Sherlock’s hair grows heavy, weighing his head down until his cheek is pressed against the duvet. If it were anyone else, Sherlock suspects the action might feel presumptuous and claustrophobic, but with John, it feels distinctly pleasant, even comforting. The extra point of contact, the additional mass. He imagines John fused to him: permanent, undeniable.

“Ready?”

Sherlock is. Of course he is.

And _oh_. It stings this time. Not the first or the second or even the third swat, unfortunately, but after that, John must finally decide that Sherlock can handle it, because the fourth is hard enough that Sherlock actually flinches and a small grunt of pain escapes his mouth.

By the tenth, his toes are curled, his thighs tense, and he’s shoved a fist into his mouth to muffle his cries. John caresses the stinging skin as the pain fades to a dull ache that is somehow immensely satisfying, even pleasurable.

It is, he thinks, very nearly perfect.

“Hey,” John says. His hand is stroking again, soothing. “Can you give me a word?”

Checking in, obviously. Ensuring that Sherlock is enjoying himself.

“Yes,” answers Sherlock. His voice is muffled by his fist, so he removes it from his mouth and lifts his head a little. “Yes. Please.”

“Good. That’s perfect, Sherlock. Another ten? How about the time between? Do you need more, maybe, or…?”

Sherlock doesn’t even have to consider. “Less. Much less.” He wants to be spanked so much that he can hardly move for the pain, so that his arse is bruised black and violet and the immensely satisfying dull ache will linger for weeks.

“All right,” John says, indulgence thick as honey in his voice. “Let’s try five seconds, then, and we can adjust as necessary.”

Five seconds is still too long. It isn’t until they get down to one second between swats—so he has time to process the pain, to cry out, and then to suck in another breath before he’s spanked again—that Sherlock is content, and by then he’s lost track of how many sets of ten he’s had.

John’s blows are also considerably harder than when they began. Each one lands somewhere slightly different on his arse than the last and sends Sherlock rocketing forwards into the duvet, wailing helplessly into his fist and relishing John’s hand in his hair, the weight on his head keeping him grounded and steady.

In no time at all, his arse is on fire. It’s not the most excruciating pain he’s ever felt, but in that moment it seems the most significant. Like a patch of pavement in the sunlight or a measuring cup left on the burner in the kitchen, he feels scalded, melted. He feels like something that should be left untouched, except that John—perfect, brilliant John—touches him without reserve, as though spanking Sherlock’s arse raw isn’t hurting his hand as much as it’s hurting Sherlock.

When the blows stop suddenly, another set of ten finished, Sherlock is only vaguely aware of it, biting and whimpering into his fist as the skin of his arse continues to sting.

“Hey. How are you doing?” John’s voice. Gentle and tender. A touch to the back of the head that glides down, grasps the side of his neck, and lifts his head. “Give me a word, sweetheart.”

_Oh god_ , Sherlock thinks, and wishes he could preserve this moment in a jar of embalming fluid and display it on the mantel: this moment when physical pain and mental ecstasy coalesce exquisitely. The present state of his neurochemistry could rival a cocaine high. He wants this daily, or at least weekly, for the rest of his life.

Sherlock opens his eyes, although he doesn’t remember closing them, and blinks repeatedly. His vision is watery. Why is it watery?

It hardly matters, he decides and nearly closes them again before he recalls what John has requested.

“John,” he says. The only word that matters. His sun, his black hole. The centre of gravity in his useless galaxy of existence. “John.”

“Yeah. I’m here.” A thumb sweeps along the underside of his jaw. “And I think you’ve had enough.”

Sherlock hasn’t. Of course he hasn’t. He’s far, far from the limits of his pain tolerance, but John only shushes him when he tries to protest.

“No.” John’s voice is soft, but there’s a degree of steel in it. “Not today. I’m not going to risk pushing you too far today. Here, come here.”

Sherlock allows himself to be hefted up and shuffled a bit until it’s no longer his bottom in John’s lap but his head, and the rest of his body is as close to being curled around John as he can manage. The position stretches the skin on his arse cheeks, which burn and throb.

He moans softly at the pain, squeezing his eyes closed, and John soothes him with wordless murmurs and brushes the hair away from his face. Sherlock has never laid his head in someone’s lap before. Has never even considered it as a potentially enjoyable activity, in fact, although clearly he’s been mistaken.

It’s exquisite. Every breath Sherlock takes is saturated with John—not only his musk, his sweat, but infinitesimal particles of dead skin cells although he cannot see or smell them. John is inside him, around him; no part of Sherlock Holmes is without John Watson.

And John wants him here. John sits perfectly still no matter how his legs must feel after all this time, and he pets Sherlock’s hair, his shoulder, his flank like he is a spoiled, cherished housecat.

Sentiment surges in him like an electric pulse, and he nuzzles John’s bare thigh, breathing in as deeply as he can—

Then Sherlock realises precisely what he is smelling: arousal. He opens his eyes to confirm, and—yes, John is very fully erect.

Sherlock isn’t. His cock is, in fact, not even remotely interested in the proceedings, and he is… only somewhat confident he can convince it otherwise in the next several minutes. The pain in Sherlock’s arse is too distracting.

_Useless_ , he thinks despairingly. _Utterly useless._ He forgot all about trying to keep himself physically aroused.

And John has noticed—surely he must have done. He is not, after all, entirely oblivious, particularly with regard to sexual matters. If this carries on much longer, he will begin to doubt Sherlock’s enjoyment and rethink the entire arrangement. Then they will return to having sex in which Sherlock is not hurt, Sherlock is not left with visible marks, and Sherlock is not cradled in John’s lap and pet and called “love” and “sweetheart.”

And suddenly Sherlock’s heart feels as though it is throwing itself again and again against his sternum like a moth against a lightbulb. Hastily, almost blind with panic, he rises and moves until he can bring his mouth to John’s prick and suck sweetly at the head.

Immediately, John hisses, and the muscles in his thighs leap beneath Sherlock’s cheek.

“Hey,” he says. “No. It’s fine. You don’t have to—”

Sherlock pulls off just long enough to aim an intense glance at John and insist, “I _want_ to.”

This time, when Sherlock takes the tip of John’s cock into his mouth, John sighs but doesn’t protest. He cradles Sherlock’s head tenderly and lets Sherlock suck until his jaw is sore and John’s entire body is stiff and trembling with the need to thrust up and fuck Sherlock’s throat until he floods it with semen.

_Do not leave_ , Sherlock thinks feverishly. _I realise I am unfit for romantic and sexual relationships, a disappointment in every possible way, the least healthful thing you could have in your life. But please—don’t leave me._

By the time John comes, Sherlock’s own cock is finally, blessedly semi-hard.

“Touch me,” he tells John, “please.”

He is promptly rolled onto his stomach, still in John’s lap, John’s grip preventing him from falling off the bed, and John wraps an arm around his waist and closes a hand around his prick, encouraging Sherlock to thrust into his tight, warm grip.

The ache in his arse is now distinctly pleasant. Not so much a pain as a reminder, like the imprint of John’s body in his armchair that Sherlock likes to mould himself to in his blackest moods.

Sherlock must look ridiculous, he thinks, humping John’s hand mindlessly, but nevertheless, John continues to cradle him like he is something precious and murmur “That’s it, sweetheart. My beautiful boy. Just like that.”

_I am_ , Sherlock thinks, _hopelessly in love with you. You cannot possibly realise the depth of it._

He comes with a whimper, feeling lost and so very, very helpless.

*

Afterwards, John slathers Sherlock’s arse cheeks in arnica cream and makes him drink a glass of water from the tap. Then he returns to the bed, near the headboard this time with his legs stretched, and lets Sherlock lie in his lap once more. His face fairly mashed against John’s belly and John’s hands in his hair, stroking gently and ceaselessly.

Sherlock lies still and quiet and drifts, content and calm in a way he can’t ever remembering being before.

“You were so good, sweetheart,” John murmurs, and Sherlock shudders, wanting to purr with pride. “Perfect, even. You have… god, Sherlock, you’ve no idea how much I adore you.”

It should fill Sherlock with glorious warmth to hear, but there’s a fissure of unease in John’s tone. There is a “but” coming. Sherlock rouses himself for it just as John begins to speak.

“Look.” John licks his lips; Sherlock can hear the wet glide of his tongue. “This is good for you, isn’t it? I mean… you enjoyed the spanking?”

A bolt of alarm rattles his calm, and Sherlock has to employ all of his self-control to remain where he is and keep his pulse from spiking and his limbs from tensing. “Yes. Surely my enjoyment was _obvious_.”

He punctuates the statement with a slow, insinuating nuzzle to John’s hip, so very close to where John’s penis is lying soft and satisfied, so that John knows precisely what he is referring to.

“There was that, yeah,” John says with a little huff of laughter. “But sometimes it just… seems like something’s off, I suppose.”

Of course it does. Because John is not a complete idiot, something for which Sherlock is usually grateful but now finds horribly inconvenient. _Why, why, must you choose now to observe?_ he thinks in dismay.

“And you know,” John continues, “it doesn’t have to be about sex. If you don’t want sex, that’s fine. We don’t have to have it.”

Sherlock squeezes his eyes closed, taking advantage of his position, his face hidden from John, to allow his expression to twist with despair. John said, not three minutes prior, that Sherlock was perfect, worthy of adoration. Why should he want anything but that, but _this_ , for however long he is allowed it?

_Do not take this from me_ , he thinks, and has to swallow a thick lump in his throat. _Please._

“I want it,” he says. Because his voice is considerably muffled by John’s skin, he tosses his head back a bit and repeats, “I _want it._ Honestly, John. Do you really think I’d push so hard if I didn’t enjoy it?”

“I never really know what you’re capable of, to be honest,” John answers. His hands resume their tender, almost reverent stroking; Sherlock didn’t even realise until now that they’d stopped. “But fair enough. I’ll trust you—and you’ll tell me if something changes, yeah?”

“Yes,” Sherlock says. “Of course.”


	4. Four

**Notes for the Chapter:**

> A couple of warnings: First, there is explicit description in this chapter of a person being cut for (consensual) pleasure. Second, this chapter features a BDSM scene gone wrong and a character dropping as a result.
> 
> Please proceed with caution if you think this may be distressing or triggering for you. Also feel free to leave me a comment if you’d like more details so you can make a more informed decision about whether to read, skim, or skip. :)

The bruising from the spanking is disappointingly minor. Rather than the excruciating sunset of colours Sherlock hoped for, the pale skin of his bottom is marred only by blotches of red that ache when he prods at them or sits directly on them.

His disappointment, however, is tempered by John’s reaction.

During the next few days, Sherlock is bent over every suitable surface in the flat, his clothing shoved aside, so John can drop to his knees, frame Sherlock’s arse between his hands, and circle his thumbs over the tender, reddened bits so softly Sherlock’s skin breaks out in goose bumps. Then, when Sherlock is so aroused and impatient he thinks he’ll scream, John gives in and dives forwards, lapping and sucking at Sherlock’s arsehole and testicles until Sherlock is so drenched with saliva it drips down his thighs.

Sometimes, when Sherlock is sufficiently wet and loosened, John stands again and glides the tip of his cock over and over Sherlock’s hole, occasionally pushing in slightly, just enough that Sherlock can feel the first hint of burning as the muscle begins to stretch, then withdrawing when Sherlock tries to rock backwards and impale himself properly.

It’s maddening, and it goes on and on until Sherlock is shaking, sobbing, and helpless to do anything but fist his prick and wail while John jerks himself to orgasm and smears his come all over Sherlock’s reddened arse cheeks.

And all the while, John murmurs things like “Fuck, your arse should be a national treasure” and “You gorgeous, magnificent creature” and “Christ, Sherlock, you have no idea how badly I want you.”

While his arse heals, and even afterwards, Sherlock takes to lounging about the flat in nothing but a dressing gown, for easier access, and he feels constantly slick and open, absolutely indecent.

He also feels distinctly cherished. Almost worthy of John’s devotion, despite his many deficiencies and his complete failure at masochism.

He isn’t even bothered that it’s been well over a week since Lestrade last summoned him to a crime scene, that he has nothing more than sex, multivitamins, and soil samples to occupy his mind. He is content: his mind a smooth, pleasantly purring engine.

John’s danger addiction, however, is apparently not so easily satisfied.

“Your inbox is bursting,” he tells Sherlock one morning as he’s preparing to leave to do the week’s shopping. “If you could at least skim through your emails before it gets too out of control….”

“Bursting” is a considerable exaggeration. Sherlock has barely 100 unopened emails, rendering his inbox nowhere near full. It’ll scarcely take a half hour to sift through them, identify and dispose of the rubbish, and arrange the remaining ones in order of his level of interest.

But John’s true meaning— _‘I need a case’_ —is clear enough.

And although Sherlock doesn’t desire a case at the moment—in fact, he wants nothing more than to research sadomasochismfurther, specifically the process by which a person might train his body to respond to painful stimuli with unfaltering physical arousal—he will nevertheless provide one for John.

So when John leaves, Sherlock changes into his blue dressing gown—his thinnest and clingiest, guaranteed to bring John to his knees when he returns—and sits at the desk with John’s computer, intent on trawling through his inbox until he’s found a case that will satisfy John’s need.

It’s easy enough to whittle down the tedious and insipid ones by subject line alone—anything with the words “love” or “fan,” usually indicating fan mail; anything that ends in an exclamation mark or an ellipsis, usually indicating general stupidity; and so on.

He’s been at it for less than ten minutes when his concentration is broken by the familiar sound of Mrs Hudson’s shoes on the stairs, followed by—ah, of course, Sherlock really should have expected this—

“Sherlock,” Mrs Hudson scolds, throwing open the door to the flat, “is it really so difficult to answer your doorbell?”

The doorbell in 221B has been broken for ages, in fact, and Sherlock rather prefers it that way. With a sigh, he shuts the laptop and scoots his chair backwards. “It is when I’ve no desire to speak to the person ringing it.”

“Charming as always, Sherlock,” says Mycroft, striding around Mrs Hudson with the tip of his umbrella clomping loudly on the floor like some sort of claw foot.

He’s lost weight, Sherlock notices, which will render any weight-based insults ineffective—they’ll only remind him of his accomplishment and make him smug.

“Thank you, Mrs Hudson,” Mycroft says with a smile so false and simpering—intentionally so, of course, he never does anything without reason—that Sherlock can’t help but roll his eyes.

It’s a clear dismissal, although Mrs Hudson glances at Sherlock, who nods at her, before actually dismissing herself. As she closes the door softly behind her and starts to descend the stairs, Sherlock stands, wrapping his dressing gown more tightly around himself.

He wishes now he’d changed into something other than the blue dressing gown, something that wouldn’t leave him feeling like a crab without its shell. His bruises and bite marks are largely healed, utterly invisible to most people, but Mycroft can still spot the subtle difference in his skin colour. Mycroft gives no sign of it, of course—his gaze doesn’t fall anywhere near Sherlock’s neck—but Sherlock knows very well that he sees.

And indeed, the first thing he says after Mrs Hudson is gone is: “I see congratulations are in order.”

Sherlock huffs. “Oh, don’t let’s pretend your feelings on the subject are at all congratulatory. And yes, intercourse _has_ been involved. I imagine you’re quite disappointed you can’t laud your no doubt _extensive_ experience now that I’m no longer a ‘virgin,’ by your rather prescriptive and dreadfully old-fashioned definition of the word.”

Mycroft’s nose wrinkles in distaste. Sherlock considers that a point in his favour and feels justified in swanning over to his armchair and seating himself with a self-satisfied flourish.

“So,” he continues, ensuring that no matter how undignified his appearance, his spine is straight and his shoulders squared, “skipping to the part where you get on with it and tell me why you’re here….”

Mycroft adjusts his own posture similarly, although he remains standing, no doubt taking great pleasure in being able to look down his overly large nose at Sherlock. “I am here because, as ever, I am concerned about you.”

Of course he is. Sherlock wants to roll his eyes again, but refrains this time. “Spare me, please, another of your lectures on the consequences of sentiment and broken hearts. My relationship”— _Do not puff up in pleasure at finally being able to use the word,_ he tells himself, but Mycroft’s raised eyebrow suggests he’s failed—“with John is none of your concern.”

“I resigned myself some time ago to the inevitability of that, Sherlock,” says Mycroft. “No, no, my concern lies instead in... certain aspects of that relationship, if you will. Your recent internet history, for instance, has been quite telling.”

Sherlock grimaces. Of course Mycroft cannot keep his fat nose out of Sherlock’s business. Like a sniffer dog, he must always scent out Sherlock’s weaknesses and expose them.

Surely Mycroft won’t attempt to involve the police in some misguided attempt at shielding Sherlock from harm. Sadomasochism is something of a legally grey area, he knows, and with Mycroft’s influence—

“Don’t be obtuse,” Mycroft says with a deep scowl. “Even if I can’t entrust you with your own safety, I can certainly entrust John Watson with it.”

Sherlock hopes that isn’t meant as any sort of reassurance, as he doesn’t find it reassuring in the slightest.

“Yes, wonderful,” he snaps, growing more bad-tempered now that he realises he hasn’t a clue what Mycroft really wants. “However, if you could get to the point, assuming that you do have one, it would be much appreciated.”

Mycroft gives him a snide smile, clearly relishing Sherlock’s discomfort, the fat git. “The _point_ , Sherlock, is that I am quite capable of seeing what John simply cannot.” The smile falls, and the snideness along with it, and then Mycroft is simply observing him, his eyes beady and shrewd. “Tell me. Do you honestly imagine you’re capable of _making_ him stay?”

Sherlock closes his eyes, breathing deeply and folding his hands as he processes the question. He sees white behind his eyelids and is vividly aware of a sudden sinking sensation in his abdomen, as though someone has slit open his belly and now his intestines are leaking out.

 _Yes_ , he wants to growl, _obviously I can’t maintain absolute control over anyone’s actions_ , at the same time that a small part of him wonders pitifully, _But why can’t I?_

Stupid. Pathetic. Sentiment is every bit the weakness that Mycroft says it is, but it is also utterly irresistible. Worse than cocaine. Worse than Lestrade at his door, summoning him to a bloodbath.

“You,” he begins, opening his eyes again, and has to clear his throat when his voice sounds small and high, like a child’s.

“Oh, Sherlock,” Mycroft says before he can carry on. There is pity dripping from his tone, and his expression—softened, his head inclined faintly—is the one that never fails to make Sherlock feel like a boy again, the idiot to his older brother’s genius. “You don’t even realise what you’re doing, do you?”

No. Sherlock hasn’t the faintest bloody clue. Obviously.

He clears his throat once more, then heaves himself to standing. “Yes, well, thrilling as this has been, I’m afraid I must ask you to _bugger off_.”

“Oh come now, brother dear. I’ve scarcely been here two minutes. Surely you—”

“ _Out!_ ”

Mycroft’s lips thin. His disapproval is a thick fog Sherlock has to remind himself not to avoid.

“Right, then,” Mycroft says after a long pause. “A piece of advice, if I may?”

As though Sherlock has any choice. He cocks his head, adopting an expression of _‘Get on with it.’_

“When you started on cocaine,” says Mycroft, “you insisted repeatedly that it wasn’t anything so serious as an _addiction_ , that you could stop at _any_ moment, that you were in _complete_ control—right up, that is, until the day you weren’t.” He smiles: a tight, forced smile. “Remember that.”

Then he leaves, with a nearly jaunty swing of his umbrella that momentarily upsets the airflow in the sitting room.

Sherlock frowns after him, then throws himself back into his armchair, clasps his hands beneath his chin, and remains there, considering. The analogy is preposterous, of course. John is not cocaine. Sherlock’s relationship with him is nothing like an addiction.

Then a new thought occurs.

 _John_.

Mycroft will go to John, now he hasn’t got the response from Sherlock that he wanted. That’s what happens, isn’t it? Sherlock is found in a drug den, and John goes to Mycroft; Sherlock behaves somewhat out of character, and Mycroft goes to John. And that cannot happen—who knows what Mycroft will say, what John will infer.

Sherlock searches his pockets for his phone—not there—and then fairly tears apart the flat in search of it before he finds it sitting in plain sight on the desk beside John’s computer. He scoops it up, then types as quickly as his thumbs can manage.

He sends to John: _Mycroft dropped by for a chat. Expressed his disapproval of certain unconventional aspects of our sexual relationship. SH_

It will bias John in his favour. Now if Mycroft seeks him out, John will be defensive, protective. Less likely to put stock in anything Mycroft says.

It’s almost three full minutes—John is an impossibly, infuriatingly slow typist—before Sherlock’s phone chimes with a response: _He’s a twat. Ignore him._

Fortunately, that’s precisely what Sherlock intends to do.

*

“I’ve been thinking,” John says.

It is, Sherlock thinks, not entirely the most appropriate time for thought.

Less than eight minutes since his orgasm, John should be a sated and sleepy body beside Sherlock’s own, capable of little but murmuring drowsily as Sherlock nestles his softened cock in the cleft of John’s bottom—still open and very, very slick from the thorough finger-fucking Sherlock gave him—and prods at the relaxed muscles in John’s back, investigating the texture as much as he can through skin, and mouths at the gnarled skin on John’s shoulder.

But, he supposes, perhaps he shouldn’t discourage John from employing his mental faculties, no matter how ill-timed.

“Hmm?” he says, laying a lingering kiss to John’s scar. _His_ scar, Sherlock is beginning to think of it as, which is irrational. It is John’s body, John’s traumatic injury, no matter how Sherlock wishes he could lay claim to it. No matter how he wishes there were nothing in John’s life that Sherlock didn’t share.

“About what you said, mm… weeks ago now, I suppose it was. You said you wanted to be cut. I’ve been thinking about that.”

At just the word, Sherlock can feel the sting of a blade sinking into his skin like a body into water. John marking Sherlock as his own, Sherlock’s blood thick and red on John’s hands. And afterwards: a road map of scars on Sherlock’s body, John tracing them with his hands and mouth, John worshipping them like he worshipped Sherlock’s arse—like Sherlock worships John’s scar.

And—Sherlock searches his mental hard drive, recovers his research on BDSM and sadomasochism— _blood play, edge play, RACK._ More serious than biting or spanking, more dangerous, higher chance that something might go wrong—infection, nerve damage, severe blood loss.

John holding Sherlock’s life in his hands. Sherlock inert beneath John’s knife, little more than a body on a slab for John to open and investigate.

The image is appealing. Why is it appealing?

Not good, Sherlock thinks. Almost certainly not healthy, getting enjoyment from the idea of being vivisected by one’s partner. _Don’t tell John_ , he tells himself firmly.

“Yes,” he says. Realises a second too late that John’s not asked a question to which “yes” is an appropriate response.

Fortunately, John doesn’t seem bothered. He swivels his head, so Sherlock can see the crinkles like starbursts at the corner of his eye and his lip curled upwards.

“You’re still interested, then?”

“Yes,” answers Sherlock. The depth of his sincerity makes his voice deep, heavy.

“Never done it before. Never really wanted to, to be honest. But I’m not opposed.”

John rolls his shoulders—no, arches towards Sherlock’s mouth. Silent request for another shoulder kiss, indication he derives as much pleasure from the act as Sherlock. Adoration fills Sherlock like fluid sucked into an eye dropper, and he bends his head to oblige.

John hums and wriggles his bum playfully. It’s surprisingly pleasurable, in primarily a mental and emotional sense, for Sherlock to press his cock against John even in a post-coital state. Intimate beyond simply the sexual.

“Do you have anything in mind?” John asks. “Any particular tools or, erm, areas or…?”

Resting his cheek between John’s scapulae, Sherlock considers. “As a veteran and a doctor, you’d be most comfortable handling—”

“No.” Giggling, John shoves Sherlock off just enough that he can flip onto his back and invite Sherlock to lie against his chest—which Sherlock promptly does, burrowing in like a tick into flesh. “Not what you think I’ll want. What _you_ want.”

Pointless. The two are the same. Whether John is keen on a dull and rusted penknife or a freshly sharpened machete, Sherlock wants whatever John will give him. No matter, he supposes: he simply needs to change his wording.

“I want… a scalpel, surgical, number 10 blade. The ones in your kit will work nicely.” And more importantly, John will be most comfortable with them. “For the wounds themselves… shallow, surface-level: scarcely any pressure on the blade while the cut is being made.” As safe as possible, obviously John’s preference. “For location… chest or hips, I think.” Areas with more muscle and fat, albeit less than if he were female. Although there are a great deal of nerves on the sides of the hips and obviously the chest is a vital area of the human body, he suspects John will be less likely to balk at those than something like the inner thigh (femoral artery) or the forearm (numerous veins close to the surface).

And indeed, John’s heartbeat remains a steady, unalarmed drum beneath Sherlock’s cheek.

“That sounds doable,” says John. “I want to look up a few things first, mind, and then talk about it a bit more, but… yeah, doable.”

 _Doable_. A vastly underrated adjective, Sherlock decides.

With a contented sigh and a grateful nuzzle of John’s sternum, Sherlock allows himself to envision the scene: the faint scent of antiseptic, the sight of John’s gloved hands—John will certainly insist on gloves—roaming Sherlock’s skin, plotting his incisions.

Perhaps John would be amenable to carving his name, or at least his initials, into Sherlock’s flesh.

He thinks about that—a _JW_ on his pectoral, flecked with dried blood, growing enflamed and irritated from the friction of his shirt against it, healing poorly and leaving him with a gloriously dark scar for John to worry with his lips and teeth—until he begins to doze.

*

John does indeed insist on wearing vinyl powder-free gloves, as well as laying a freshly disinfected tarpaulin atop the bed and ordering Sherlock to lie on his back in the centre of it. Once Sherlock is properly situated, John proceeds to disinfect him as well, using antiseptic he nicked from the clinic earlier that day.

They’ve decided on the left hip as the area to be cut. They’ve also, over the last several days, decided on numerous other details of the scene—Sherlock will wear no blindfold or bindings; John will remain unthreatening, caring, and attentive; Sherlock requires no preparation or foreplay aside from whatever John deems necessary to ensure Sherlock’s safety; their phones have been silenced and Mrs Hudson has been informed that they’re not to be bothered until further notice.

There were also determinations made about lighting, bandage types, something involving biscuits, and other things, but by that point Sherlock had stopped paying attention. All of it is immaterial, as far as he’s concerned. He is present, he will do what John says, and John will cut him; everything else is noise.

“How’s that?” John asks, tossing the final used cotton wool onto the bedside table with all the others. “All right?”

Sherlock blinks up as John kneels on the tarpaulin beside him. It’s precisely like he envisioned—the gloves, the antiseptic—yet it’s also not. The smell is sharper, almost nauseating, and reminds him strongly of a hospital, and the gloves are unnerving, seeming to belong to someone else now that Sherlock can no longer see the torn and uneven fingernails, the nearly imperceptible gun calluses on John’s fingertips, the simple patterns of wrinkles on John’s knuckles.

“It’s… surprisingly clinical,” says Sherlock, and realises only when John’s open expression dims with concern that he perhaps shouldn’t have said so. “But fine,” he adds hastily. “Good. Not a problem.”

And it won’t be, he promises himself. If John insists on clean and safe, then Sherlock will oblige him. More than that, he will endeavour to make this a pleasant experience for John. Better than the spanking, better than the biting.

That Sherlock isn’t erect—nor is John, for that matter—is unfortunate, but not irreparable. They’ve not started yet, after all. Everything will be fine, Sherlock thinks.

It will all be fine.

“Are you sure?” John says, frowning now. “If you’re not comfortable—”

“It’s _fine_.” Sherlock ensures his gaze is unwavering, resembling something easily mistaken for honesty, and nearly sighs in relief when John nods.

“Okay,” John says, his expression clearing. “That’s good. Erm… shall we get started, then?”

 _Finally_.

“Yes,” Sherlock answers.

While John reaches for his medical kit and prepares the scalpel, Sherlock shifts a little on the tarpaulin. He will, of course, have to remain utterly still while John cuts him and even afterwards while John cleans and bandages him. Best to make himself as comfortable as possible now.

When he feels a cautious touch to his left hip, Sherlock gains a sudden appreciation for the aptness of the idiom _to leap out of one’s skin._ His surprise seems to come like a blast from some hidden corner of his skeleton, and the violent jolting of his limbs seems his body’s attempt to contain it.

“Hey,” John says, sounding alarmed, and Sherlock opens his eyes—when did he close them, he didn’t mean to close them—to see John’s face pinched with worry. “Hey, it’s all right; it’s just my hand. Are you sure you’re okay?”

“Of course.” Sherlock wills his muscles to relax and is relieved when they acquiesce, falling limp and allowing his skin to mould itself to the tarpaulin. “I’m fine.”

 _You aren’t_ , some treacherous part of his mind—sounds rather like Mycroft, actually—insists. _Listen to your pulse, your breathing rate—you’re frightened, anxious._

Is Sherlock anxious? Why is he anxious?

 _Because you asked for this. He’s doing this for you, because he thinks this will arouse you, and you know very well that it won’t. Because your intentions have little to do with sex, and just think how he will look at you when he knows how incompatible you and he are, how very horrifying and_ unhealthy _some of your desires—_

John lays a gloved hand just below Sherlock’s sternum, pressing gently down and massaging his skin reassuringly, soothingly. The scalpel is abandoned, somewhere out of sight. Sherlock takes a deep, calming breath, summoning the mental image of John’s initials in his skin and the memory of John pawing at his reddened arse, loving the sight of Sherlock marked by him just as much as Sherlock loved the sensation.

“We can stop,” John says, still rubbing at Sherlock’s skin. “It’s no problem. There’s nothing wrong with changing your mind, you know. Or we can try again another time if you—”

Sherlock cuts him off with an indignant huff and begins to sit up. “For god’s sake. No. As I said, I’m _fine_. I was only momentarily—”

Then he glances down and sees that John isn’t rubbing at a random bit of skin on Sherlock’s torso, but rather at the scar there. Subconsciously, no doubt, since John has shown no signs of fixating on it before now—in fact, has seemed quite determined not to so much as acknowledge its existence, so Sherlock has allowed himself to almost forget that it is there.

“Shit,” John says, after glancing down as well, and yanks his hand hastily away. “Sorry. I wasn’t—erm, wasn’t really paying attention. God. Sorry. I didn’t mean to make you uncomfortable.”

Why should it make Sherlock uncomfortable? On the contrary, the sight of his own scar and the reminder of the bullet that made it is oddly comforting.

Both Sherlock’s worst failing and his greatest success, in that scar.

Because Sherlock has never failed John as spectacularly as he did with Mary. Countless indications of Mary’s true identity missed because Sherlock refused to let himself fully deduce her. He didn’t want to see her flaws and all the bits of her that didn’t line up perfectly with John, to fixate on them, and to live with the knowledge that John was marrying someone flawed who didn’t suit him as well as Sherlock.

Cowardly and selfish. He’d stared at Mary, the gun in her hand, and hated himself fiercely for failing John when John needed him most.

But, then: the first crack in John’s Sherlockless happily-ever-after. Well, less of a crack, more of a massive cannonball through the wall. And then: John hauling his things up the stairs to 221B with his noose-like fists and his shoulders like a wooden shelf that had been broken and repaired so many times it could barely still hang. All trust in Mary destroyed, all trust in Sherlock restored.

For that reason alone, it is the best of Sherlock’s numerous scars.

And now, while Sherlock stares down at it, still feeling the ghost of John’s touch—it gathers together all the pieces of Sherlock’s shattered composure, and his heartbeat finally slows, his breathing evens out.

 _John has killed for me,_ he thinks fondly. _He would have, despite his claims to the contrary, named his child after me had she survived to be born. And now, he is mine, in nearly every way one person can belong to another._

“I want you to cut me,” he says thickly. “Please.”

John’s eyes widen. Sherlock supposes it must seem an unusually abrupt subject change, from the topic of his scar back to the real issue at hand, and he should have perhaps taken steps to make it seem less…erratic. Nothing for it now, though.

“I’m not sure,” John says slowly, “that that’s a good id—”

“ _Please_ ,” Sherlock insists.

He can see the moment when John gives in. How his eyes go soft and his shoulders, straight and tense, slump slightly, and he smiles. A small one, just a hint of an upwards quirk of John’s lip, but it’s as significant as a speck of dirt on a dead man’s trainer. Sherlock would rather like to place that small smile in a bag and declare it evidence so that everyone understands its significance.

“Okay,” John says. “We’ll carry on. But I want you to tell me immediately if you change your mind. Do you remember your safeword?”

“Hydrochloric,” Sherlock replies dutifully, and experiences a tiny thrill when John nods in satisfaction.

“Good.” Another thrill, larger this time. “And if you can’t manage that one for some reason, a ‘no’ or a ‘stop’ or even a pained sound will do.”

With that settled, John touches Sherlock’s left hip again, and this time, Sherlock doesn’t jump. He simply swivels his head to the side, so he has a better view of John’s hands, still gloved, gently kneading Sherlock’s skin.

“Is three still all right?”

Three? Sherlock doesn’t recall anything involving the number three. Possibly something discussed in one of the endless negotiating conversations he deleted. Doesn’t matter, really, he supposes. John is in charge.

“Yes,” he says. “Fine.”

John wets his bottom lip with a quick swipe of his tongue, and his eyes narrow, his forehead wrinkling as he concentrates. Superimposing his knowledge of human anatomy onto Sherlock’s body, plotting his first incision.

There’s nothing particularly erotic about that, yet a faint shiver runs through Sherlock’s abdomen and his groin feels suddenly tight. His eyelids flutter closed as he savours the sensation: the very first thin tendril of arousal beginning to unfurl.

 _Oh, yes_ , he thinks with a shudder. Perhaps this will prove successful after all.

He keeps his eyes closed, focusing on that feeling, letting his very capable mind supply the image of John stroking back and forth over his skin, warming it up in addition to searching out the best location to cut.

“I think I’m going to make the first one,” John says, “right here.”

A pointed poke just above the widest part of Sherlock’s hip, then John’s fingertip drags sideways—well, vertically for him, but sideways for Sherlock—and lifts.

“Light and slow,” John continues. “Just like we talked about. I’ll just barely break skin. Then we’ll see how you’re doing and if you want me to carry on.”

Sherlock makes a soft noise of understanding and agreement, and John’s hands return to his hip, flattening the skin again and holding it taut.

The blade of the scalpel is cool. Not so much that it’s jarring or unpleasant, but enough so that Sherlock is very aware of the moment it makes contact with his flesh. He holds his breath, waits for the first bite of pain as his skin is split, but it doesn’t come immediately. Not until the scalpel begins its slow, painstaking journey across his hip, following the exact path that John traced, and then the sting finally blooms, trailing just behind the blade.

Sherlock is vaguely aware of the scalpel disappearing, leaving him with only the pain, but it seems unimportant—inevitable, which of course it is. It’s not awful, the hurt isn’t. It’s not really anything, actually: just… pain.

“How was that?” John asks. “The scalpel’s sharp, so it might take the pain a bit to register.”

Yes. The pain continues to grow as Sherlock lies here, basking in it, sucking it in like smoke. Still, it’s weak. And even with his eyes closed, he knows it isn’t bleeding. If it were, the blood would be leaking down his hip; he would feel it. He doesn’t.

He considers opening his eyes for confirmation, but decides he doesn’t want to see. Not yet.

“I’m not bleeding,” he says instead.

“There’s blood in it,” John answers. “Not enough that it’s dripping or anything, but there _is_ blood. Are you okay?”

Barely a scrape, then. It’ll take less than a week to heal, and it won’t scar. Disappointment roils in his chest. Well, Sherlock supposes, he did say “scarcely any pressure on the blade.” So it’s his own fault, really.

“Do the next one harder,” he says. There’s a sulky pout in his tone, and he clears his throat to rid himself of it. “I want it to bleed.”

The mattress shifts beneath him and the tarpaulin makes a rough crinkling noise as John crawls closer to Sherlock’s head and taps one gloved finger against his right cheek. It smells overwhelmingly of hospital: vinyl and antiseptic. Sherlock wrinkles his nose in displeasure.

“Do me a favour, love,” John murmurs, “and open your eyes for a second.”

Warmth: a great wave of it in his chest, like settling down in front of a roaring fire. Sherlock couldn’t say no, not to that word, even if he wanted to.

He opens his eyes, and his vision is filled with John. John’s greying hair, his thin lips, the wrinkles around his mouth and at the corners of his eyes. John’s eyes… impossible to pinpoint the colour. John will answer blue when asked, but that’s not the whole of it. There’s a ring of darkish yellow around the pupil that, at times, makes his irises appear hazel. Now, however, his eyes look more greyish green.

They are, Sherlock thinks, the most aesthetically pleasing eyes he has ever seen. Never predictable, never dull.

John smiles at him, and Sherlock is helpless but to smile back.

“Hello there,” John says. “You didn’t answer my question. Are you okay?”

Sherlock blinks, remembers suddenly where he is and why, and is surprised how for even a moment he could forget.

“Yes,” he says. “I’m fine.” Then, just to ensure John understands: “I want the next one to be deeper.”

John laughs. It’s mostly breath, which smells of mint toothpaste and is hot on Sherlock’s face.

“Okay. I can do that. I just… wanted to be sure you were all right.” Still smiling, John bends forwards and presses a kiss to Sherlock’s forehead, then nuzzles his fringe so sweetly that affection floods Sherlock’s body, as fast-acting and potent as cyanide. “You’re doing so well, by the way. You didn’t move at all while I cut you.”

Ridiculous, perhaps, how satisfying it is to hear, but Sherlock hardly cares. He moans softly, happily, and closes his eyes again when John eventually draws back and returns to Sherlock’s hip.

“I’ll make the second one just above the first,” John says, and, just like last time, drags a finger across Sherlock’s skin to illustrate.

Sherlock nods to indicate his agreement, and then John is stretching his skin and keeping it taut while he positions the scalpel.

This time, it hurts immediately. Either because Sherlock isn’t expecting it after last time or because John actually presses down a little, sinking the blade into Sherlock’s skin before he begins to move it. But whatever the reason, Sherlock’s toes curl at the sting and his jaw clenches, holding in a pained hiss.

Fortunately, it’s over soon. Then the blade is gone, and, with it, the worst of the sting, leaving Sherlock with a deep throbbing ache not unlike the sensation that followed his spanking. Except this one is even more satisfying: more concentrated, less overpowering. He can feel the blood welling up in the fresh cut, collecting in little beads along its length, and then falling down his hip and onto the tarpaulin.

It’s exquisite, although the sensations are difficult to catalogue. Like when he first met John: nothing wholly unfamiliar, nothing he hadn’t experienced before, but there was a gravity to it, an indescribable difference from the usual that—although nearly imperceptible—was hopelessly alluring, impossible to ignore.

_Oh, John Watson, it’s always you._

“Hey.”

John’s hands frame Sherlock’s face, thumbs stroking just beneath Sherlock’s eyes, which he opens obligingly. The first thing he sees is John’s thumbs, both still vinyl-covered. The right is smeared with red. Sherlock’s blood.

For a moment, Sherlock is filled with such delight that his chest feels tight. His breathing stutters.

“Still all right?” John asks. “How does that feel?”

It feels fantastic. Isn’t that obvious?

But no, Sherlock realises abruptly, of course it isn’t obvious: Sherlock isn’t erect. His penis lies entirely flaccid between his thighs. Even the tendril of arousal he felt earlier is gone.

But _why_? Why does Sherlock’s body remain dull and limp while his mind sparks and lights like a firework? It’s inexplicable and _stupid._

“Sherlock?”

With a jolt, Sherlock refocuses his attention on John: his greyish-green eyes, his Sherlock-smeared thumb.

“I’m fine,” Sherlock assures him. “It feels… remarkably satisfying.”

That earns him a smile: small but fond. “Remarkably, hm? That’s good. You’re doing perfectly, sweetheart. Still want the last one?”

Last one? Ah, that must have been what John meant by “three.” Sherlock has one more chance, then, to convince his transport to cooperate.

“Yes,” he says. “Similar depth as the second, I think.”

“Okay, love.”

John kisses his forehead again and then, oddly, pauses to do the same to Sherlock’s chest, just above his scar, before he returns to his previous position near Sherlock’s hip and takes up the scalpel again.

Sherlock turns towards the ceiling and closes his eyes, conjuring the most erotic memory he has: his first sexual encounter with John. John backing him rather forcefully into the wall, rising onto his toes to reach Sherlock’s mouth, his lips tasting of whiskey, his hands roaming greedily under Sherlock’s shirt.

Relocating to the bed—Sherlock had to be quite literally dragged because he wanted John _then_ , didn’t want to wait and risk losing him—and John allowing Sherlock to climb on top of him, John giggling into Sherlock’s mouth like Sherlock was dangerous and intoxicating, John moaning into Sherlock’s shoulder and saying, “Christ, Sherlock, that’s hot. Make that sound again, please? God, you sound even better than I thought you would.”

The fire licking at Sherlock’s veins, the desperation gnawing at his bones, the question spinning round and round his mind as John sucked so sweetly at his cock that Sherlock’s calves tensed and cramped: _How long? How long did you think about this? How much time did I waste craving you when I could have had you just like this? Oh god, please, John, I need it, let me come—_

The fresh sting of a scalpel sinking into his skin jars Sherlock from the memory. He inhales sharply and is overwhelmed by the scent of antiseptic, of hospital. He opens his eyes slightly, squinting up at the ceiling as the blade begins to drag across his skin.

This time, he is vividly aware of the blood pooling immediately in the cut, collecting in drops that slowly trickle down and onto the tarpaulin, compelled by gravity to fall.

He’s on his back. Falling backwards. Molly’s voice, solemn: _‘On your back, gravity’s working for us.’_

 _No,_ Sherlock thinks fiercely. _Not that. Not now. Think about something else. Think about the ache, the blood. Your blood, leaking out—_

But that’s worse. The thoughts come faster: Blood loss. The unshattered mirror. The cork in the bottle, blocking the blood flow, Sherlock hasn’t been murdered yet, the bullet’s still inside him. _Because you_ chose _her, you wanted_ her _. Your way, John._ Always _your way._

“Sherlock?”

Sherlock starts—realises he’s been staring dumbly at the ceiling, lost in the darkest recesses of his memory, while John finishes the third cut. That John is bending over him, ripping off his gloves with something like panic on his face.

 _You’ve panicked him_ , Sherlock thinks, blinking rapidly. The image of Mary with her gun lingers behind his eyelids, refusing to be dispelled. _Well done. You’ve ruined it. You are surely, by this point, the worst sexual partner he has ever had._

“Hey, look at me.”

John’s hands cup his throat, his left thumb skittering over Sherlock’s carotid artery. Monitoring his pulse. As though Sherlock is swooning, as though he’s suffering anywhere near enough blood loss for his pulse to be affected.

“It’s okay,” John says. He’s practically cooing. “You’re okay. Come here.”

Then Sherlock’s head is being cradled against John’s chest, John’s fingers raking tenderly through his hair.

“I’m fine,” Sherlock insists, although he doesn’t pull away. Can’t even summon the energy to attempt to, even though he knows he should. He’s endured torture, bullet wounds, broken limbs, and survived unscathed, untraumatised—three minor cuts should not incapacitate him, should not make him feel as though someone has stuck a metal pick up his nose into his skull and scrambled everything about.

 _This was_ , he thinks, _a horrible idea._

He can’t even fathom any longer what the appeal of this was meant to be. All he’s gained from the endeavour are three shallow cuts in a neat little column on his hip. They will heal quickly. If any of them scar, it will be faint, only noticeable in certain lighting and only to him.

Not to mention, they are not John’s name or initials. They aren’t the shape of his teeth or nails. Sherlock hasn’t left anything of himself on John’s body; the blood-stained gloves are already removed, soon to be binned with the rest of the rubbish. Sherlock isn’t tied any more to John now than he was before they began.

_‘Do you honestly imagine you’re capable of making him stay?’_

Sherlock flinches, nearly recoils, and is stopped only by John’s grip, which is gentle but unyielding.

“You don’t have to be fine, you know,” John says. He’s fairly crushing Sherlock to him now. It should feel pleasant. Sherlock should feel like a treasure hoard, awe-inspiring and well-protected.

Instead, he feels like an elaborate hoax. He wishes he could melt through John’s skin and mould himself against John’s skeleton so that nothing but John could ever touch him again.

But of course, John wouldn’t want that. John wouldn’t want that at all.

“You can be a mess,” John continues. “Overwhelmed, confused… anything, really. I’m sorry. I thought three might be a bit much for the first go. I should’ve listened to myself.”

John will never cut him again, Sherlock realises. Not now that he’s ruined everything. It will be like their former favourite Thai restaurant where Sherlock argued with the waitress one time and got them thrown out, and now every time Sherlock suggests it for dinner, John sighs and tells him, _‘Do you remember what happened last time? Because I do, Sherlock, and we are_ never _eating there again.’_

Sherlock will never see John’s hands coated in his blood. He’ll never convince John to carve his initials into Sherlock’s flesh. He’ll never get the fierce, bone-deep pleasure of knowing that John has marked him so vividly and permanently that someone someday might use the scars to identify his corpse.

Because Sherlock insisted on this, went along with it, although he knew very well that his body wasn’t yet trained to respond to pain as a proper masochist would. Stupid, selfish, and impulsive.

 _‘You always were so stupid,’_ Mycroft would say. _‘Such a disappointment.’_

 _Fix it,_ Sherlock thinks.

He tries to worm from John’s embrace, and after a moment of hesitation, John allows it although he clearly isn’t happy about it. His hands linger on Sherlock’s shoulders, fingertips trailing over the skin until they have to drop away.

“I want to suck you,” Sherlock says. He shams a pout, ensuring that his bottom lip is plumped enticingly. (John likes that, he knows; John has on two occasions kissed and sucked Sherlock’s bottom lip while murmuring, “Christ, this lip. I fucking love this lip. Makes me want you on your knees.”)

He reaches for John’s cock—entirely soft, of course, because how could he still be aroused with Sherlock behaving like this, but Sherlock can rectify that easily enough. However, John stops him, clasping Sherlock’s hand and holding it immobile between them.

“Ta,” he says calmly. But it’s a false calm; Sherlock can see the tension in his jaw. “But I’m not much in the mood just now.”

Sherlock sees white, feels alarm rise like a tide in his throat. He’s not only turned John off the idea of hurting Sherlock, but sex with Sherlock altogether. “You’re not interested in getting off?”

“No. A bit more interested in making sure my boyfriend’s okay, to be honest.”

 _Boyfriend._ He’s said it—he’s actually said it. Sherlock should be pleased about that; he should be thrilled.

Instead, he feels his eyes begin to burn, his vision to blur. Surely he isn’t getting upset. Why is he getting upset?

He cannot let John see. Who knows what John will think?

“I’ve just remembered,” Sherlock says, jerking backwards and turning his face away.

He slips slightly on the tarpaulin, and the skin of his left hip immediately flares with pain and starts to throb. Sherlock glances down, sees the cuts and the thin dried streaks of blood, and his thoughts scatter like shards of shattered glass. They’re lovely, even if they’re not deep and not obviously John’s. So very lovely. Red: colour of passion, anger, danger—

 _Not now_ , Sherlock tells himself, frantically retrieving his thoughts. What is wrong with him? It’s as though his mind has been deluged with malware; it whirs and whirs and accomplishes nothing. “I need to see Lestrade about—”

“Not now you don’t,” says John, following him and laying a hand on Sherlock’s shoulder to keep him seated. “I need to clean and bandage your cuts, then you need to eat some biscuits and drink something.”

Sherlock has hardly lost enough blood to warrant that, but he isn’t given the chance to protest before John is speaking again.

“But for right now, just come here. I’ll feel loads better after I’ve had my arms around you for a bit, yeah? Come here, sweetheart.”

It’s the pet name, spoken in such a tender tone, that does it. A tangle of sentiment, composed of too many emotions to bother identifying, forms in Sherlock’s throat.

He crumples, allows John to gather him up like a distraught child and coo meaningless platitudes, telling him “It’s all right, love. You’re okay. That’s it, sweetheart, I’ve got you.”

 _Yes, but for how long?_ Sherlock thinks in despair. He knows that John is loyal, John is faithful, yet at the same time, he can’t help but wonder how long he has before John cuts him loose: lets him float alone and rot and sink like an abandoned ship at sea.


	5. Five

“You’re fixating, brother dear,” says Mycroft. “You know what happens when you fixate.”

Sherlock stares into his tea. It’s still steaming, the sides of the delicate china cup nearly burning his fingers where he is gripping it. He grinds his teeth, and doesn’t answer.

“You _miss_ things. Surely you remember the burglary in Manchester? The animal fur in the kitchen that didn’t matter one whit, although you’d convinced yourself it was _crucial_ to the case simply because it was so very interesti—”

“Sherlock?”

Sherlock blinks, and Mycroft’s voice is silenced, his tea is lukewarm, and John is standing in front of him, peering down at him, the skin between his brows puckered with worry. Sherlock’s mobile phone is balanced on the arm of his chair, its screen still illuminated and displaying Mycroft’s latest text message ( _Don’t you remember what happens when you fixate? MH_ ).

“Yes?” he says, shifting his fingers on the tea cup.

“Are you okay? How are you feeling?”

Not quite 20 hours since the scalpel debacle, countless cups of tea and plates of sandwiches and biscuits, and John hovering in Sherlock’s sight as ever-present and quiet as a ghost, and Sherlock feels… off. Dimmed, somehow. As though he’s standing constantly behind a wall of scratched, mud-speckled glass.

All he says, however, is “Fine,” as he sips his tea.

John’s facial muscles momentarily contort into something like an expression of irritation and then fall neutral again. He doesn’t like the answer, obviously.

Fine. Sherlock has done nothing but cock this up since the beginning he is clearly unequipped to carry on without assistance. _Just tell me what to do_ , he mentally pleads, _and I will do it. Anything at all._

With a heavy sigh, John sinks into his own chair across from Sherlock’s. The distance is nearly unbearable. Sherlock wants to stretch as far as possible across the carpet and brush a leg of John’s chair with his toe.

“Right,” John says. “In that case, we need to talk.”

All the oxygen might’ve been sucked from the room, for how difficult it suddenly is to breathe without gasping desperately and clawing at his chest in panic. Sherlock considers himself largely ignorant of the language of intimate relationships, but even he knows those words herald disaster.

Swallowing thickly, he sets his teacup aside and folds his hands in front of him. He is pleased, considerably so, that his tone is even when he asks, “What about?”

“For starters, about how you being ‘fine’ is the biggest load of cack I’ve ever heard.”

John pauses, his gaze shrewd, as though he expects Sherlock to deny it. Sherlock has no intention of doing so, however, and as the silence lingers, John’s eyes soften before he continues.

“Look. For… god, weeks now, I think, I’ve had this… feeling like something was off with you, with us really, but I thought….”

John shakes his head, licking his lips. Sherlock is achingly familiar with the particular sort of despondency on his face, the brittle set of his shoulders, although he’d hoped that after John moved (permanently) back to Baker Street he would never wear that expression again.

“Do you know what it’s like to have to second-guess everything your significant other says to you? To live in constant suspicion that you’re being lied to by someone you’re supposed to trust more than anyone else?”

Sherlock doesn’t. Of course he doesn’t. He shakes his head, feeling lowly and impotent.

“It’s _exhausting_ , Sherlock. At a certain point, you just sort of… well, you stop paying attention, I suppose. You shove it aside, you make yourself stop caring, because it feels like you’ll go mad if you don’t. Eventually, looking the other way becomes second nature, although you don’t even really realise you’re doing it—until something forces you to step back and look at yourself, that is.”

Sherlock closes his eyes, remembering the first time John moved (temporarily) back to Baker Street. How he sat in his chair, perfectly straight and still like a statue, and stared at nothing and asked, _‘Do you think there’s something wrong with me, that I can hate someone and still love them at the same time?’_

(And Sherlock answered that there wasn’t, of course. There’s nothing wrong with John at all. John is the closest to perfection that Sherlock has ever known.)

“I haven’t—” Sherlock says, opening his eyes again. But no, he can hardly say he hasn’t lied, can he? “I’m not—” But no, neither can he say he’s not like Mary. Isn’t John telling him right now that he is?

John shakes his head. “It’s fine, it’s just… I stopped trusting myself, so I let things go far, far too long when I should’ve seen right away that something was wrong. And I don’t know what’s wrong, exactly. I have ideas, mind, but nothing concrete. So I’m going to ask you right now, and I’d really appreciate it if you were honest with me. What happened last night?”

_Be honest_ , Sherlock thinks. _Just be out and done with it._

He steels himself, inhaling deeply and preparing to speak.

But what on earth, he wonders, is he meant to say? _‘I was reminded of the time your dead wife shot me, and I became inexplicably upset’? ‘I failed to become aroused, despite finding the experience mostly enjoyable (with the notable exception of the end), and I became alarmed by the seeming incompatibility of our sexual interests’? ‘I’m sorry. Some of the things I want would horrify you, and I don’t know why I want them. I know I shouldn’t. I’m sorry. I’m so terribly sorry. I don’t know what I want’?_

“I don’t know,” he says, sounding small and pitiful: an embarrassment. “I’m—I don’t—”

“Okay,” says John, looking patient. So very patient and attentive, while Sherlock is a disaster who cannot construct a single useful sentence, much less the veritable speech that would be required if he were to explain everything. “It’s okay. If you don’t know or you don’t… if you aren’t comfortable talking about it, that’s—”

Another brief spasm of John’s facial muscles, although this time it’s hurt and disappointment that flit across his expression. Sherlock feels ill.

“—that’s fine,” John finishes. “Well, not _fine_ , exactly, but I understand.”

_Say something_ , Sherlock thinks, distraught. Words spin in his mind like bits of upset dust, but they refuse to fall where his mouth can find them. His throat works and his jaw clenches, useless. _For god’s sake, he wants you to speak._ He feels trapped, panic like a column of water climbing up his body.

“I understand,” John says again, emphatically. “But for now, maybe we should take some of the, erm, the sex things off the table.”

“The sadomasochism,” Sherlock says. A child could hear the dismay in his voice, but he hardly cares. _Look at you,_ he thinks. _You’ve ruined everything._

John blinks, clearly taken aback. “Er, yeah. That. Sherlock, it’s… I just don’t think it’s working right now. Which isn’t to say that we can’t try again in—”

For a moment, Sherlock hears nothing but static, which seems to echo throughout his body like a scream in a hollow room.

_This is precisely what Mycroft means_ , he realises. _You’re fixating. Millions of satisfying romantic relationships thrive without sadomasochism, without sex at all even. It doesn’t matter. Be content with it. Do not complicate it._

“Sherlock? Is that… are you okay?”

Sherlock starts, bringing the moment back sharply into focus. He nearly answers yes, that he’s fine, but… no. No.

“I don’t know,” he says. Perfectly truthful.

John’s smile is kind and empathetic. Despite himself, Sherlock feels slightly warmed by the sight. “Okay,” he answers softly.

Then he stands and steps closer, so he can run his hands through Sherlock’s hair. Sherlock lets himself be coaxed to the edge of his seat and rests his forehead against John’s jumper, in the soft space just below his ribs. He can hear the very faint throb of John’s heart and the gurgling of his stomach.

“It’s okay,” says John. “It’s all okay. We’ll figure it out.”

*

Nothing is okay.

John insists on checking his cuts every night, but he does so with the clinical dispassion of a GP, not the awed and worshipful manner from after Sherlock’s spanking—even though the cuts become gloriously red and puffed-up, like claw marks. (Sherlock spends an entire morning in the bathroom admiring them in the mirror, envisioning John on his knees before him, kissing and licking at them and staring up at Sherlock with a reverent, adoring expression.)

There’s a distance that didn’t exist before, a sort of stiffness to their interactions, although the difference is so subtle Sherlock struggles to quantify it. There is affection, yes—John nuzzles him and kisses him and murmurs happily when Sherlock rolls to his side of bed during the night—but there’s a hesitancy, an awkwardness, that makes Sherlock want to shout and pull his hair out in distress.

John still, at least, continues to sleep in Sherlock’s bed, and shows no indication he’s considering moving his things back upstairs. Sherlock clings to that, and clings even more fiercely as the days pass and John doesn’t initiate sex even once.

He lies awake at night, watching John snuffle in his sleep, and remembers how easy it was to die for John, to come back for John. Standing on the roof of Bart’s, John’s tinny voice in his ear telling him that he could be that clever. Entering the restaurant two years later and spying John’s face across the room, so beautiful and familiar despite the abominable new facial hair, and experiencing such a wave of boundless, hopeless love he could have sobbed with it.

Sherlock remembers all of this and huddles closer to John’s sleeping form and feels every bit the broken, bloody body on the pavement after he’d jumped, not the man who had stood up and straightened his coat and walked away.

Lestrade doesn’t text with a case. Sherlock’s inbox is scarcely better: nothing capable of holding his attention for longer than ten seconds, certainly nothing like a proper distraction from the mess with John. Even Mycroft leaves him well enough alone.

So when Molly, apparently back from her holiday, texts to say that she’s saved him a bag of toes if he’s interested, Sherlock fairly leaps at the opportunity.

“Case?” John asks, standing in the kitchen threshold while Sherlock buttons his coat and arranges his scarf around his neck.

“Hm? No. Molly’s offered me a bag of toes. I’m off to Bart’s to fetch them.”

Sherlock puts his gloves on and then pauses for a moment, fiddling with them as though he’s brushing off lint and doing a quick buff of the leather. Waiting for the comment that should follow: a quip about his hobbies, a plea to find better storage than the vegetable crisper this time, a threat to dispose of the toes if Sherlock fails to follow John’s rigid “safety and cleanliness” protocols.

However, John says none of those things. He only nods curtly and mutters, “Ah. Right.” He flexes the fingers of his left hand once and then clenches them into a tight fist. Sherlock can see from his expression that he feels awkward, uncertain.

It hurts. John Watson should never feel uncertain in Sherlock’s presence.

_Say something,_ he tells himself. _For god’s sake, say something._

“I’ll be home for dinner,” he says.

And is promptly so horrified with himself he would gladly swallow his own tongue if he were capable.

A domestic thing to say, frightfully so, and Sherlock is not domestic. Mary was, at least for a time, and look how that turned out. John cycling to work, discontent, seeking out danger in drug dens—and then everything else, of course. Sherlock does not want to be like Mary, not any more than he already is. He can’t be.

“Oh, right,” says John, his eyes widening in surprise. “That’s… good.”

Sherlock leaves before he’s given any further opportunity to make an idiot of himself.

The entire way to Bart’s, he considers the possibility that he should be actively looking for a new case: something dangerous and exciting, something that will mend the fissure between him and John that his own idiocy has caused. Something that will ensure Sherlock is meeting a need that Mary, even at her and John’s happiest, did not.

He needn’t even put much effort into locating a suitable case, he realises. After all, although Sherlock isn’t satisfied by anything less than a six, John has shown numerous times that he enjoys a case as low as a two. Any number of the discarded cases in his inbox—all of them deleted at the moment, but fortunately a deleted email is easy enough to retrieve—will surely suffice.

Or there could be something on the blog. Sherlock hasn’t checked today.

He nearly pulls his phone from his coat pocket to have a look, but by then, the cab has arrived at Bart’s. So he leaves it where it is, pays the cabbie, and carries on inside.

Afterwards, then. He’ll get the toes from Molly, return to the flat, find a case for John, and everything will be better. John may be doomed to a relationship of sexual and emotional dissatisfaction, but Sherlock can at least give him this.

Molly is pleased to see him. She always is, of course. Her admiration has long since abated to something of a more platonic nature, but still she glows when she catches sight of him across the lab and sets her scalpel down so eagerly it makes a clanging noise and nearly rolls onto the floor.

_Scalpel_. Sherlock is reminded of the cuts on his hip. The pain of them has all but faded, unless he picks and worries at them—which he often does and suddenly feels compelled to do now.

As Molly hurriedly removes her protective gear, Sherlock slips his hands in the pockets of his coat, allowing the left one to scrape his hip, digging into his trousers which press against his pants which puts pressure on the wounds.

They ache. Just slightly, just enough.

_John_ , he thinks, reverent. Yes, he’ll find a case as soon as he’s finished here. John will grin at him, be amazed by him, chase after him: panting and vibrant and _happy_.

“Hello, sorry,” Molly says as she approaches, smelling strongly of antiseptic wash and smiling. “Didn’t expect you so soon. Fortunately, I hadn’t really got started yet.”

Sherlock suspects he should feel badly about interrupting, although he doesn’t. She texted him, after all, not the other way round. He removes his hands from his pockets, momentarily lamenting the loss of pressure against the cuts.

“Molly.” He nods in greeting, striving for politeness even though he’d prefer to rudely retrieve his toes and leave, return to John and his newfound mission. But politeness is necessary when someone is doing you a favour—one of the many things John has taught him. “You look….”

Sherlock considers her. Paler and four pounds lighter than when he last saw her, and her usual smile and cheerful glow are considerably muted. No, she isn’t well.

Nevertheless: polite.

“Well,” he finishes. “You look well. How’s…”

Name, he needs a name. Not Tom: that was the last fiancé. Not Jeremy: that was one of the boyfriends after Tom. Sherlock pictures their flat last Christmas. John standing beside him in a horrible Christmas jumper—blue and red and white, with a pattern of repeating reindeer and snowflakes, the one that inspired numerous fantasies in which Sherlock ripped it from John’s body and then fucked him atop the tattered ruins of it. John, practically effusive in comparison to Sherlock’s polite but disinterested welcome, offering his hand to Molly’s fiancé and repeating his name. John’s voice, warmed by a glass and a half of wine: _‘Nice to meet you—’_

“Richard?” Sherlock says, quite confident he’s got it right.

Molly’s smile becomes tight; her gaze flickers to the floor. “Oh, he’s… he’s fine. Still a bit knackered from the trip, even worse than I was. We went to Italy! Er, I don’t know if you remember that. I told you, but… um.”

Relationship in trouble, obviously. The stress of travel, multiple weeks in the near-constant presence of one another, it revealed issues of which neither was previously aware. The engagement will almost certainly be called off within the month, if not this week. By him, of course.

But Sherlock will say nothing on the subject. Because it is not in fact kinder to tell people when their romantic entanglements are doomed to fail. He’s learned that from John as well.

“How’s John?” Molly asks, and Sherlock exhales, blinks, and returns to the moment, to the lab, to Molly.

“Fine. John is fine. He—”

Then Sherlock recalls the flow of the conversation and stops, startled. The art of small talk involves reciprocation and finding commonalities, which means that Molly asking after John immediately after Sherlock has asked after her fiancé is significant.

But that doesn’t make sense. Although Sherlock’s person isn’t entirely devoid of any indication of his and John’s relationship, the signs—the dusting of John’s hair on his coat, the faint scent of John’s aftershave still lingering on his collar, his previous fondling of the sex wounds on his hip—are subtle enough he doubts Molly, clever though she is, is capable of spotting them.

No. More likely, she mentally cast about for something that would be comparable to Sherlock’s inquiry into Richard’s wellbeing and settled on John only for lack of any other option.

Nevertheless, it reminds him of Donovan’s and Lestrade’s failure to observe. And now—no John. No need to concern himself with subtlety.

“Actually,” he says, and finds himself standing straighter, fighting the urge to puff himself up like a peacock. It’s not as though it’s something to be proud of. He’s finally got his first boyfriend at age forty, and not quite four months in, he’s already doing a fantastic job of cocking it up.

Still: John in his bed, John’s things mixed in with his own, John calling him “love,” John’s marks on his hip. _John._

“John and I,” he continues, “are in a relationship.”

It feels momentous. Like a bomb has dropped, whiting out everything in its path and leaving a faint buzzing in Sherlock’s ears, like that of a single bee in a silent room.

That Molly appears utterly unaffected by the pronouncement is baffling, to say the least. Perhaps “relationship” is too ambiguous?

“A romantic and sexual relationship,” Sherlock amends.

A little wrinkle appears between Molly’s eyebrows. Indicating confusion, Sherlock notes: not surprise. “Okay,” she says.

Only one possible conclusion to be drawn: “You already knew.”

Molly’s confusion deepens. “Well… yeah. It’s been a bit, erm, obvious, hasn’t it? Since probably a year ago, at least. Sorry, um, was it meant to be a secret? Because it’s fine, you know, really! We none of us mind. The people who care about you, that is.”

A year ago? Prior to 109 days (and 17 hours and six minutes) ago, Sherlock was John’s best friend, nothing more. It couldn’t have been _obvious_ because there was nothing to be obvious about!

Is this why Lestrade was so nonchalant about the bite marks on his neck? Has he too spent the last twelve or more months believing Sherlock and John to be in a relationship—so convinced that they have long been romantically involved that he is unmoved by physical, incontrovertible proof of it?

_It doesn’t matter_ , Sherlock tells himself. _Of course it doesn’t matter._

But it does—why? Why does it matter?

“Are you all right?” Molly shifts her weight anxiously, biting her bottom lip with an uncertain squinty and part-flinching expression. “Was that… was that wrong to say? I’m sorry! I didn’t mean anything by it, I really didn’t. Just that who you are and who you—”

Sherlock stops listening, stepping back and rubbing his temples and struggling to breathe. He needs to sit; he needs to think. One year of “obvious,” when he spent every moment analysing every aspect of John’s behaviour from every possible angle and found evidence of nothing but platonic admiration and the occasional stray sexual thought and masturbatory fantasy? What did he miss? He must’ve missed something, and how long has he been missing it, and for god’s sake, _why does it matter?_

“Sherlock?” Molly is suddenly closer, gripping his bicep as though he’s in any danger of collapsing. “Did something happen? Did… did you and John have an argument?”

Dear god, why is Sherlock still here? He was meant to pick up a bag of toes, not have a heart-to-heart with Molly about John. He needn’t have even bothered with Molly. He knows very well where she keeps the body parts that she saves for him; he should have fetched them and then been off. He could be back in a taxi by now, scouring his inbox for a case.

“Do you want to talk about it?” Molly persists. “Maybe I could help.”

“‘Help’?” Sherlock scoffs. He can’t even fathom it: Sherlock confiding in Molly about his failure as a masochist and a healthy sexual partner, Molly counselling Sherlock about romance. “What advice could you possibly offer? One failed engagement already and another one imminent, not to mention a dating history that includes being used by a criminal mastermind. You consistently idealise your partners and remain blind to any qualities that might—”

“Yes, exactly,” Molly snaps, her face gone pink and her lips tight. “I’ve had loads of experience with relationships going tits-up, so maybe you should stop being an insufferable arsehole and _listen_ to what I have to say so yours doesn’t do the same.”

_My relationship_ , Sherlock nearly snarls, _is hardly going ‘tits-up_ , _’_ but then he recalls that after almost four months of constant sexual activity, it’s been nearly a week of nothing more than a cuddle, and the indignation leaves him like a mouthful of cigarette smoke.

“It’s… difficult to explain,” he eventually offers.

Molly nods encouragingly. “Well, I have time for you to try anyway. Mr Davies certainly isn’t going anywhere.” Then, with the hand still on Sherlock’s coat arm, she leads him to a pair of wooden stools nearby.

Sherlock feels ridiculous, like a schoolboy having to explain his behaviour to the headmistress, but nevertheless, he sits in the stool she gestures him towards and clears his throat, preparing to explain.

Although he can’t explain all of it, of course. The sex, the spanking, the cutting, he can’t imagine she wants to hear any of that—or that she even needs to, in fact, in order to understand.

“It’s recently come to my attention,” Sherlock begins, “that John and I are not—” He sifts through words, discarding them as poor fits, until he’s left with the one that makes him wince to say aloud, despite having thought it so often in the last several weeks. “— _compatible_ in certain aspects.”

“John told you that?”

“Of course not.” The absurdity of that—John using those words, John even implying them, the man who has in the entire time Sherlock has known him always been the one who is dumped despite all the women he dated who bored him half to tears—makes him snort. “It’s obvious. I observed it.”

“But he agreed when you brought it up?”

Sherlock nearly flinches at the scene conjured by that question. And to think that mere days ago he was entertaining the possibility of telling John everything. Which would be worse, he wonders: John responding, _‘Oh, yeah… guess that might be a problem,’_ or John denying any sort of incompatibility while his body language betrays him?

Aloud, Sherlock simply says, “Why would I bring it up?”

Molly cocks her head and screws up her face in puzzlement. “So that you could discuss it? Maybe try to find some way to compromise? That’s, um… sort of how a relationship works. Communication, and honesty.”

_Ah, yes_ , Sherlock thinks sadly _. And I’ve failed spectacularly at that as well._

“If you’re worried about how he’ll respond,” says Molly. “I mean, I don’t know him as well as you do, obviously, but from what I _do_ know, he seems the type who’d rather you told him about your concerns instead of letting them fester. I certainly don’t think he’d do anything drastic like… well, leave you over them.”

“Leave me?” The idea is so laughable Sherlock can’t summon the restraint to hold in a bark of laughter. “Not likely, not if he has even an inkling that I am still committed.” Which Sherlock always will be. Obviously. “John is unfailingly loyal. By the time that Mary died, John had lost all trust in her, and still he was absolutely, unshakeably loyal until the very end. It’s both his greatest virtue and his greatest flaw.”

He can hear the tangled thread of emotion in his voice. The memory is surprisingly raw, considering Mary wasn’t _his_ wife; he never had anywhere near the degree of affection for her that John did. No reason for it to still smart, yet it does, a bit.

“Well, that’s certainly something you shouldn’t be doing,” says Molly, and Sherlock can see that she is forcing herself to be cheerful, to keep her chin raised and her tone positive. “Comparing yourself to Mary, that is. All of that, that’s nothing to do with you and John.”

She doesn’t understand. Of course she doesn’t; Sherlock only barely understands, so why should he expect anyone else to? He’s struck with the urge to tug at his hair in frustration, but reins it in. Sucks in a deep breath and prepares to elucidate.

“You didn’t,” he begins, then has to pause, when the breath he’s just taken seems suddenly to abandon him. His lungs burn; his entire chest cavity feels tight. He inhales again, then tries to push past.

“You didn’t see how it was. Nor… nor everything that happened because of it.”

Sherlock remembers. John’s perpetually sullen expression, the sagging line of his shoulders, the slow formation of near-cavernous bags beneath his eyes, aging him more than even the moustache and the worst of his PTSD had done.

It would destroy Sherlock if the same happened while John was romantically involved with him. Discovering John in bed with someone else would hurt less.

He keeps these thoughts to himself, but Molly’s soft, kind gaze and the slight twist of her lips into an almost-grimace indicate she’s at least deduced the general sentiment of his thoughts.

“What did Mary do to lose John’s trust?” she asks.

“Lied. Obviously. John is tolerant of any number of faults.” _Arrogance, showing off, tendency to leave a mess and never make the tea_ , Sherlock thinks with fondness. “But never lying.Lying about things of importance, anyway,” he amends. “Her very identity, in this case.”

Molly stares, wearing a wide-eyed tight-lipped expression like she’s waiting for something, although Sherlock has nothing else to add. Finally, she sighs. “You… you don’t even see the problem with any of this, do you? Don’t… don’t take this the wrong way, but for a genius, you really are… um.”

“An idiot?” Sherlock offers wryly, and experiences a bright flare in his chest at the image it conjures: that first case with John. On the pavement, John smiling at him, delight like a current rushing through Sherlock as he smiled back, inhaling deeply until he could detect that faint—very, very faint, no one but he and Mycroft would be able to smell it—scent of gunpowder on John’s skin and clothes.

Sherlock has adored John Watson ever since. His short doctor-soldier, his blogger, his conductor of light, his best friend and flatmate and partner, his anchor and anti-noise. His everything.

“I see the problem,” he admits softly. “Failing to admit my ‘concerns’ is lying by omission. John would find it reprehensible. Perhaps not as reprehensible as Mary’s actions, but nevertheless—”

“Then stop being a knob and talk to him,” Molly says, so harshly that Sherlock blinks rapidly, taken aback. “If you’ve enough energy to waste on comparing yourself to Mary, you can afford to spend some of it on trying _not_ to muck up like she did.”

_He mightn’t have stayed_ , Sherlock thinks suddenly, and it’s like a sliver of light in a pitch-black stairway. It both illuminates and casts shadows on the wall that make him want to hide his face in fear. _If she’d told him early in the relationship, before he’d got terribly attached. A trained assassin: the very concept is enough to offend his strong moral principle. He might have left. It might’ve been enough to override his loyalty and his devotion. Don’t you_ see _? I think, I believe, but even I don’t_ know _. I never know for certain what he’ll do._

But once she’s finished speaking, Molly stands from her stool as though the conversation is over, so Sherlock swallows it all and stands as well, gathering his coat more tightly around himself.

“Another one imminent?” asks Molly, as Sherlock adjusts his scarf.

“What?”

“You said one failed engagement and another one imminent.” She glances briefly towards her feet and then back up to meet Sherlock’s gaze, confident almost to the point of defiance. “You think Richard’s going to break it off?”

He regrets saying it quite keenly now, but there’s no point in pretending he didn’t.

“Break it off yourself before he has the chance,” he tells her solemnly. “You’ll be better off without him. He hates cats, you know. He’s a horrible fit for you.”

Molly’s eyebrows arch high on her forehead. “He doesn’t!”

“Of course he does. The location and pattern of your cat’s fur on his clothes at Christmas made it obvious enough. Very helpful, pet fur—you can always tell an animal lover from a person who barely tolerates them. Now—” Sherlock tosses his fringe from his forehead and grants Molly what he hopes is an appropriately bright, friendly grin. “—the toes?”

*

When Sherlock returns to the flat, carrying just a little less than a dozen middle toes in a food storage bag inside a Tesco bag, John is seated in his armchair with a book. One of Sherlock’s, by the looks—yes, definitely, he can see the empty space on the bookshelf. Oh, he must be so _bored_ if he’s resorted to raiding Sherlock’s bookshelves.

After the discussion with Molly, Sherlock forgot all about finding him a case. Regrettable, even disgraceful. He’ll do it now, then, after he’s rearranged the contents of the fridge so he can store the toes in the crisper.

“That didn’t take long,” John says, closing his book and setting it on the chair arm as Sherlock sweeps into the kitchen.

“I said I’d be back by dinner.”

“Which means nothing, really, since we don’t have a regular dinnertime. So I just assumed that meant you’d be back at some point before midnight.”

Sherlock is hardly responsible for John’s assumptions, and he opens his mouth to say as much.

Only to close it again, his teeth making a cartoonish clacking sound, a second later when he throws open the fridge door and sees inside it.

It’s been cleaned since Sherlock was here earlier. Not only does the plastic smell overwhelmingly of cleaning product, but everything’s been rearranged and sealed in plastic storage bags. On a whim, Sherlock peeks into the crisper and finds it empty, although he knows this morning it contained at least one tomato and part of a head of lettuce.

After a little poking about, he locates both food items at the very back of the fridge, behind John’s remaining three cans of beer.

He drops the toes into the crisper, closes the fridge, and then goes to the sitting room, where John’s taken up the book again and is flipping idly through its pages.

“You cleaned.”

John glances up, a little shadow of confusion falling over his features. “Beg your pardon?” Then: clarity peeks through like the sun through the clouds. “Oh, the fridge. Yeah, well. Knew you were bringing body parts home, so I moved things round a bit. I know _you_ don’t mind if your dinner’s been mashed up against some dead bloke’s bits for a week, but I’d rather they were kept as separate as possible, thanks.”

Firstly, Sherlock has not stored any sexual organs, much less the genitalia themselves, in the fridge since John has lived with him. Secondly, and most importantly, John has never accepted Sherlock bringing home body parts without a row of some kind: John banging on about sanitation and hygiene and _normalcy_ and storming off in a strop when Sherlock refuses to remove the offending body parts from the flat.

“You—” Sherlock begins, but finds that his vocal folds are not cooperating. He sounds choked, or ill. He clears his throat and tries again. “You hate when I keep experiments in the kitchen.” It is, in fact, one of the few topics that has never failed to make John red-faced and shouty.

John again sets the book aside and then turns in his chair so that he’s facing Sherlock, who is standing awkwardly in the centre of the room. Still in his coat and scarf, he realises, although he can’t be arsed at the moment to care.

“And still, you keep doing it,” John says, sounding only slightly put-out by that. “So, there you go. This is my compromise. I might buy another plastic bin or two to keep in the fridge for this sort of thing. Although why you can’t just buy a separate storage unit—” He stops suddenly, and his expression twists. “Sherlock? What’s wrong?”

Sherlock doesn’t know. (For god’s sake, why does he _never_ _know_ anymore?) The knot of unease he’s been carrying in his mind like a tumour these last several days constricts suddenly and begins to throb. He’s struck with an impulse to fall to his knees and crawl to John, lay his cheek on John’s thigh, and tell John in excruciating detail how very much Sherlock’s heart is no longer his own and hasn’t been for years.

_It’s yours_ , he imagines confessing. _All of it. You’ve conquered it, collared it, made it kneel obediently at your feet—by doing nothing more than existing. Oh, John Watson, will you never stop surprising me?_

There’s a whisper of Mycroft’s voice in Sherlock’s mind— _‘Do you honestly imagine you’re capable of making him stay?’_ —but it’s washed out by Molly’s: _‘Maybe try to find some way to compromise? That’s, um… sort of how a relationship works.’_

He has no intention of following Molly’s advice, certainly not at this moment and maybe not ever, but somehow when he tries to tell John that he’s fine, nothing is wrong, why would something be wrong, he thinks, _That’s clearly a lie, don’t lie, he doesn’t like that_ , and what comes out instead is:

“I’m not a masochist.”

Momentous. The second bomb dropped in a single day, although this time Sherlock squeezes his eyes closed so he doesn’t have to witness the impact, the precise moment of devastation. Safe in his bunker, he’ll emerge to greet whatever life is left when the worst of the danger has passed.

The silence stretches, heavy and thunderous.

Then: John says, “Okay.”

And he sounds so unaffected, so matter-of-fact, that Sherlock has to reopen his eyes and look.

There’s nothing extraordinary in what he sees. It’s essentially the same sight he closed his eyes to: John in his chair with Sherlock’s book— _The Penal System: An Introduction_ , says its cover—balanced on one arm. John’s expression is open, his emotions plain in the configuration of facial wrinkles, the shape of his mouth, the set of his jaw, the degree and direction of his head tilt: interest, curiosity, concern, patience, uncertainty.

“Is that…” John pauses, licking his lips. “Is that meant to bother me?”

A fissure of exasperation. Sherlock concentrates on the familiarity: John not understanding, John not being able to keep up.

“You’re a sadist,” Sherlock explains. “You derive physical pleasure from inflicting mild, consensual pain on others.”

Another emotion joins the rest on John’s face: disconcertment, visible in the amount of space between his eyebrows. “That’s… oversimplifying a lot, but okay.”

“You become aroused when I am bitten, scratched, or spanked,” Sherlock says. His breathing, he notices almost abstractly, has quickened, but he feels oddly calm now. “I don’t. Therefore, you are a sadist, and I am not a masochist.”

“Again,” John says, “massively oversimplifying.” Sherlock can hear in his tone that his patience is stretching, splintering, but still John clings to it, stubborn. “But fine. It arouses me, but it doesn’t arouse you. So what?”

“ _So_.” A swift burst of anger, and Sherlock stops speaking to temper it. John is not being deliberately obtuse; he simply doesn’t understand. He cannot fathom how it will kill Sherlock if John never hurts him again. “So, even though it doesn’t arouse me, I… enjoy being hurt by you.”

John puckers his lips and squints, an expression of exaggerated confusion. “Okay.” He draws out the second syllable and adds a questioning lilt at the end. “That’s… well, I’d started to wonder a bit, to be honest, but…. Have I been making you feel pressured? Even if you think you enjoy something, it doesn’t mean you have to _want_ —”

“Ugh!” This time, the frustration is a hot bolt down his spine, and Sherlock digs the fingers of both hands into his hair and _shakes,_ tossing strands of it all about and no doubt making an absolute mess of his curls, but it helps, keeps him at least slightly contained. “No. I _want it_. It’s immensely pleasurable for me in ways I cannot quantify. I’ve tried to maintain physical arousal, because you’ve made your position on that quite clear, but—”

“I’ve—hang on, what?” Suddenly tense with agitation, John twists his upper body more fully towards Sherlock. “What position? And how did I make it clear?”

Sherlock adopts a Johnlike pose, a Johnlike expression, and a perfectly Johnlike tone. “‘Kind of nice, actually. Being hurt _during sex_.’ ‘If that’s the sort of thing that _gets you off_.’” He drops the act, returning to his own voice and mannerisms and waving his hand emphatically. “Pain is acceptable during sex, if it gets you off. Wanting pain outside a strictly sexual context is unacceptable, _unhealthy_.”

John grips the arms of his chair hard enough his fingers leave visible indentions in the fabric, and he uses that to heave himself into a standing position, his entire body practically rigid with frustration. “I never said that! Christ, Sherlock, I never even meant to _imply_ it. That’s not what I think at all, and I certainly don’t think there’s anything wrong with you if you don’t _get off_ on pain. I—”

John cuts himself off, staring wide-eyed at Sherlock, and Sherlock realises that he is cowering. That he is very obviously afraid, and John no doubt misunderstands. John can be intimidating and physically imposing, but never with Sherlock. Usually, in fact, it is with people who threaten Sherlock, and then he is small and quiet and utterly terrifying, but that’s not what is happening here.

Here, Sherlock has buggered up spectacularly, and if John leaves, he will be nothing.

John inhales shakily and takes a single step backwards, looking away. “Okay,” he tells the wall. “Okay, we… god, you haven’t even taken your coat off. Look, I’m… I’m going to make tea, because I think we could both use some tea, and then we’re finally going to get this sorted. So. Just take off your coat, sit down, and I’ll… I’ll be back in a tick, all right?”

John leaves the room without waiting for a response. Which is fortunate, as Sherlock isn’t sure what response to give. He suspects _‘Please don’t leave my sight, I’m not sure I could bear it’_ wouldn’t be well received.

So while John is in the kitchen, Sherlock removes his coat and scarf, hangs them both neatly up, and sits in his armchair across from John’s while he waits. Remembers John in his lap, discussing limits and safewords, John coddling him and trailing his hands over Sherlock’s bitten throat. He was so hopeful then. So certain he was doing well, behaving perfectly.

If this conversation goes poorly, he thinks, he may never be able to drink tea again.

“Here.”

John approaches with a steaming mug, which Sherlock accepts and then holds gingerly while John drags over the little end table for him to set it on. Sherlock promptly does so, fully intending to let it sit until it’s cooled to the point of being undrinkable.

“All right,” John says, sitting in his armchair with his own steaming mug. He’s told Sherlock multiple times that tea calms him, centres him, in times of high emotion, but he’s mistaken. It’s not the tea itself, but the act of making tea. He’s not taken so much as a tiny sip—it’s still too hot for that—and already he’s regained his confidence and his composure. “First of all, you… look, I see now I shouldn’t have just assumed you knew all this. But not all kink or BDSM or whatnot is sexual. There’s nothing unacceptable or unhealthy about wanting a bit of pain outside a sexual context. Not so long as you’re honest about it, you satisfy that desire at least reasonably safely, and—”

_Dear god,_ Sherlock thinks, wanting dearly to roll his eyes and sigh long-sufferingly, _it’s the useless Google search all over again._ All the tripe about honesty and trust and respect, and if he has to listen to John’s verbal rendition of it, he doesn’t know what he’ll be reduced to.

“Yes, yes,” he says testily, “it’s fine with you. Excellent, sorted, moving on. _You_ get off on it. _I_ don’t.”

Which is, Sherlock realises abruptly and no doubt belatedly, the true crux of the matter.

But… not entirely accurate, is it?

“Well,” Sherlock amends hastily, “yes, I _do_ get off on it, a bit, but not… not immediately. Not until afterwards, with the marks and the pain when I’m healing….”

And that’s where it breaks down: cracks and shatters and is ground to dust. His body always twenty steps behind his mind, his body a tedious and slow and _stupid_ thing that can never hope to catch up. His mind thrives without food or sleep, and his body lags until his hateful biological processes overwhelm his mental ones and make him ill. His mind lights like a Christmas tree and revels in the pain of John’s hand, teeth, and nails, and his body collapses like a stalled engine.

“Yeah,” John says softly, “I’ve noticed that. The bit about the marks and the healing, that is. You sort of… light up afterwards, I suppose is one way to describe it. It’s… I’ve never seen anything like it.”

Sherlock realises with an unpleasant start that his eyes are closed, that he’s leaning forwards with his hands in his hair again like a melodramatic wreck of a person. His body’s further betrayal. He reins it in immediately, removing his hands and straightening his spine and opening his eyes, focusing on John: John’s kind face and unfathomable irises.

“You,” John begins, then pauses. Licks his lips, the bottom one turned down at one corner in thought. He sets his mug on his thigh, holding it steady with one hand on the rim. “You can’t possibly think I mind. Jesus, Sherlock. That you like it at _all_ , that’s… you don’t even have to do _that_ to make me happy, you know. You definitely don’t have to try to ‘maintain physical arousal’ or worry about either of us getting off or—”

“I _want_ to get you off,” Sherlock snaps. “I want you to be _satisfied_.”

And immediately wishes he’d said nothing, because John’s eyes go wide and then narrow, his lips disappear as he presses them tightly together. He’s employing Sherlock’s methods, and even if he fails—he quite likely will, he’s hopeless at deduction—he at least knows there’s something to deduce.

After a brief, startlingly intense silence, John takes a deep breath. “Fucking hell, Sherlock. Since the very beginning, you’ve been carrying on like some sort of martyr, haven’t you? I’ve been worried I was imagining things and inventing problems where there were none, and meanwhile you’ve been suffering in silence and thinking you’re somehow making everything easier for me.”

Sherlock frowns, offended. “I’ve hardly been _suffering_.”

John ignores him. His face is growing faintly red, his lip beginning to curl into a kind of half-snarl. “You great fucking knob. It’s not all about you. You’re not the only person in this relationship, and you aren’t the only one who gets a say in what sort of relationship we have.”

“You get _aroused_ ,” Sherlock protests. The column of water, the panic, is back, up to his chin this time. He tightens his lips, struggles to swallow and breathe despite the pressure. “You’re _erect_.”

“You definitely don’t get to decide what sort of sex I want,” says John, looking close to furious now. “You think I like worrying that I’ve pushed you into something you don’t want? You think I like not being able to say for certain whether you’ve enjoyed something or not?”

Of course not. Not John: kind, considerate, selfless John. _But you weren’t supposed to know_ , Sherlock thinks. His eyes burn, and he blinks rapidly. _I didn’t mean for this to happen_.

“You’re angry,” he blurts. Stupidly. Obviously John is angry, and perhaps rightfully so, and good god, what sort of thing is that to say in a conversation like this?

“Yes,” John says shortly. “I am a bit. But it’s not helping anything, is it? So I’m just going to….” He sighs, shaking his head, and the fury slowly fades from his expression. After a brief silence, he shifts his weight, leaning forwards in his chair and looking earnest and intent. “Look, here’s the thing about my being aroused. Do you know when you are absolutely, overwhelmingly, _devastatingly_ sexy to me?”

It’s perhaps the last question Sherlock expects. He feels impossibly small and dumb in front of it. He shakes his head.

“At a crime scene.” John’s gaze flickers, drifting off somewhere above Sherlock’s head as he thinks. “Particularly a crime scene we’re specifically invited to, where there are dozens of officers waiting for you to get on with it and out of their way. You’re an arrogant arsehole. Acting like you’re better than everyone. Swanning about with your collar up and your coat swishing.”

“It doesn’t _swish._ ”

“It does.” John laughs, his gaze returning to Sherlock and his eyes squinty and glowing with faint amusement. “It does, and it’s… it’s _hot_ , Sherlock. It’s stupidly hot. It makes me want to get down on my knees and offer you any orifice you please, but I don’t, do I? Because it’s not the time for it. And that’s fine. I can have you afterwards, a day later or a week later, after the case is done, and it’s just as good as if I’d had you immediately. Do you understand?”

Sherlock does. Or, at least, he understands what John intends for him to understand, although John—kind-hearted, simple-minded John—doesn’t see all that Sherlock sees. The numerous flaws in the analogy, the jagged edges, the little blemishes in the surface just begging to be picked at.

“You know,” John says, when Sherlock doesn’t immediately respond. “I had an interesting conversation with Mycroft the other day.”

Panic. Like a harpoon through his stomach, a tight metal chain wound round and round his ribcage. Of course Mycroft went to John. Sherlock even knew that he would, although he never saw any sign of it. Because Mycroft is stupidly clever, of course, and remarkably adept at subterfuge when he wants to be.

_‘Do you honestly imagine you’re capable of making him stay?’_

“About what?” Sherlock’s tone is thankfully even, almost sufficiently aloof.

“A load of stuff I thought was complete rot until now. Although, to be fair, I suppose I was reacting more to his tone than what he was saying. He talked about you like you were some sort of child, or maybe an overly eager puppy, which pissed me right off, and the words ‘hopeless’ and ‘naïve’ got thrown about too much for my liking. So I didn’t pay him much attention at first.”

John takes a sip of tea, then returns to balancing the mug on his thigh. Gripping it like he would a glass of whisky. Subconsciously longing for a drink, dear _god_ , look what Sherlock has done to him.

“But now, finally, I realise,” John continues, “just how badly I ballsed this up in the beginning, if you honestly think you’re in danger of doing anything that’ll put me off permanently.”

A spark of… aggravation, exasperation, disbelief, dismay, _something_ hits Sherlock right in the chest and pumps him full of adrenaline, restlessness, useless energy, and he can’t remain both seated and standoffish much longer, something will have to give, so he surges to his feet to pace.

“So all of that about your _concerns_ ,” Sherlock says, and oh, his tone isn’t good. Not standoffish at all, he sounds emotional, distraught, a rickety little bridge on the verge of collapse. “All of that about your relationship with Mary being _unhealthy_ , about how you _can’t do that again_ , that was all _bollocks_ , was it? Unimportant? Not actually a concern at all?”

John shakes his head, leaning forwards so he can slide his tea onto the table alongside Sherlock’s. “It was me being a twat, and giving in to irrational fears because the whole mess of my marriage was apparently more traumatic than I realised. But for fuck’s sake, Sherlock.” He laughs, a little forced huff of breath that means he really doesn’t think any of this is funny at all. “You can’t honestly tell me you think we’re going to end up like Mary and I did.”

“Of course we are!” Sherlock shouts, surprising them both. He doesn’t mean to say it, doesn’t even realise he’s in danger of saying it until it’s left his mouth. And then, well. If he’s going to ruin everything, why not piss on the wreckage as well? “You haven’t the faintest _idea_ what I would do to keep you. If it were between killing an innocent bystander and losing you forever, I wouldn’t even hesitate. If I’d been in her place, I’d have shot me too. More than that, I wouldn’t have missed—I’d have made certain the shot was fatal, that _no one_ could take you away from me.”

“No you fucking wouldn’t have.”

With a shaky breath, Sherlock drops his hands and looks at John, who’s still sitting down although with one elbow on the arm of the chair and his cheek propped in his hand, confident and casual as you please. “I beg your pardon?”

“You’re an idiot,” John says calmly. “You’re actually the biggest idiot I’ve ever met because you know _shit_ about yourself. I mean, you think you’re a sociopath.”

“I am a sociopath,” Sherlock insists, albeit weakly. “High-functioning, but nonetheless.”

That earns him a chuckle, John baring his teeth in amusement. “You will take any case, no matter how ‘dull,’ if you think someone is being abused. You get upset when people are cruel to animals, and violent when anyone dares to threaten Mrs Hudson. And I’ve never had sex with anyone who made me feel half as adored and cherished as you do. You’re the least sociopathic person I know.”

Sherlock says nothing. Isn’t even capable of saying anything. He stares down at the floor, his tongue feeling unusually thick and limp in his mouth.

“You may be able to see through everything and everyone,” says John, without any amusement now, “but you’ve never been able to see yourself. And that’s fine, because I do see you, and I know you’re not like Mary. Well, not like _that_ , anyway. If you were, we wouldn’t be having this conversation right now.”

_Not necessarily_ , Sherlock thinks. _I’m cleverer than she was, after all, and I learned a great deal from her failure._ But even as he is thinking it, he feels the knot in his mind finally begin to loosen and unfurl. Enough so that he can inhale shakily and say, “You’ve been… distant. I thought—”

“ _I’ve_ been distant?” John’s eyebrow arches like a scythe, grim and devastating, and his lip curls upwards to complement it. “I’ve been following _your_ cues, actually, which was clearly a shit thing to do. Now I know better.”

Sherlock mentally reviews his behaviour over the last few days. It could, he supposes, perhaps be considered distant, but… he’s sure that he was only responding to John. That John withdrew, became hesitant and stiff—

“Oh for god’s sake,” John sighs, “come here.”

Sherlock blinks, confused, but does as John has requested, shuffling towards him. Then John sits back a bit, spreading and extending his arms in a clear invitation for Sherlock to situate himself between them, and Sherlock understands.

He practically scampers into the chair atop John, wedging his knees between each chair arm and either side of John’s hips. But his legs are hatefully long, and he’s too far away: his arse planted on John’s knees, John’s head ages from his own.

So he shifts his weight to his knees, hefts up so John’s face is level with his rectus abdominis, and does his best to ensure his entire upper body is folded around John’s. Swaddling him, encasing him, sheltering him: the best thing in Sherlock’s life, the only thing worth protecting. And John, for his part, bows his head so he’s fairly nuzzling Sherlock’s stomach, and his arms wind around Sherlock’s waist, fingers closing around handfuls of Sherlock’s shirt as though anchoring him, keeping him there.

When Sherlock dies and is buried, he decides, he wants that on his tombstone: _‘William Sherlock Scott Holmes. John Watson once thought he was worth keeping.’_

They won’t be able to maintain this position for long, of course. Sherlock’s knees are already sinking uncomfortably into the chair, and his legs and feet will soon be cramped and numb, as will John’s. But for now it’s tolerable.

“You have no fucking clue, do you,” says John. His voice is muffled considerably by Sherlock’s shirt and skin, but still understandable. “You let me think you were dead for two years. You didn’t understand at all why I might be a smidge upset when you came back as though nothing had happened. You’ve drugged me. You’ve drugged _yourself_. You’re fundamentally incapable of making a decent cup of tea, or coffee, or _anything_ for that matter. I’ve lost countless articles of clothing to your experiments. I’ve cleaned animal remains from the tub and human remains from the fridge, and held your cock while you had a piss and wiped your arse after a shit because you’d gone and poisoned yourself like a _knob_ and couldn’t manage on your own.”

“That was entirely accidental,” Sherlock protests, but John carries on as though he’s not spoken at all.

“And still, after all that and more, I’m completely _mad_ about you. I’ve never loved anything as much as I love you, and that you honestly don’t know that is… I’m sorry. I’m sorry I didn’t think to say it until now.”

It feels as though Sherlock’s heart swells in his chest. Larger than his lungs, larger than his whole body even. He curls himself even tighter around John, cradling John’s head against him, his fingers mapping all the bones of John’s skull: frontal, parietal. Oh, the parietal. The shape of it moulds perfectly to Sherlock’s palm.

“I don’t care if pain doesn’t get you off,” John says. His breath is hot, seeping into the fabric of Sherlock’s shirt. “I wouldn’t even care if you hated it, and never wanted to be spanked or bitten or anything again. It’s really not the kink for me you apparently think it is.”

“But you do enjoy it,” Sherlock feels compelled to remind him. “In that sense, it is a kink for you.”

“Sure. But I enjoy a lot of things. Like how you tease me with that gorgeous bottom lip of yours. Or your love affair with my scar. Or how you take my cock like it’s nothing—almost no one’s done that, you know; even a lot of women have been at least a bit intimidated.”

Intimidated? John’s penis is no larger than the ones Sherlock’s seen in pornography, but at the moment, he supposes it hardly matters. In the grand scheme of the conversation, it’s a minor detail, so Sherlock only hums encouragingly and tries in vain to squirm even closer.

“You know what else I’d enjoy? Knowing a bit more about what _you_ like, to be honest. I’d… really, really be interested to hear more about that, actually.”

He can hear the truth of it in John’s tone. Sherlock squeezes his eyes shut, nearly overcome, and continues mapping.

Occipital, temporal. Beneath the bone: the temporal lobe, the lateral sulcus, the insular cortex. John’s affection for him lives there, Sherlock thinks. All the emotion that makes John _mad_ about Sherlock, makes him _love_ Sherlock, originates there. If Sherlock could, he would peel back the bone and tissue that contains it and kiss it, worship it, thank it for enabling John’s attachment to him—for allowing Sherlock to have this.

“You’re not even paying attention, are you?”

“Of course I am,” Sherlock assures him. Then, to prove it, he summarises: “You want me to be honest about my sexual interests.” And he can do that, he tells himself. He can. “I like being marked. I like after you hurt me, the… the aftercare. When you—” The words form, and he flinches at the thought of them.

“Yeah?” says John.

“When you coddle me,” Sherlock admits, softly. “When you call me soppy names and tell me what you think of me.”

“About how gorgeous you are, you mean?” John’s voice is as warm and expansive as his breath, finding its way into every crevice of Sherlock’s body and burrowing in. “You like when I tell you how bloody fucking perfect you are? There’s nothing wrong with that, you know. And you don’t have to be hurt for me to do all that. I’d be just as happy to call you soppy names and coddle you without all the rest of it.”

Of course he would. Sherlock’s obliging, endlessly affectionate John.

But it’s more complicated than that. Harder to explain, if not impossible. Sherlock’s not been able to pin it down in his own mind, so how is he meant to say it aloud?

Nevertheless, because John wants it—because John is mad about him, John loves him, John enjoys a lot of things—Sherlock tries. “I want—” _Crime scene: DNA, contusions, blood stains, gasping sobbing body shattered beneath you._ “I want to be _broken_. I want to be hurt so badly that I—” _Can’t move, can’t even breathe without remembering in explicit detail how you tore this dull, hateful body into pieces and rebuilt it into something interesting._ “That I forget everything except you, and myself. I want—” _To be yours. Always yours, John._ “I want to feel like I’m yours. I want to be helpless and vulnerable, beaten and bloody, limp and mouldable as clay in your arms while you tell me I’m yours.”

But even as he’s saying it, he knows it doesn’t make sense. His desires are as foreign and abstract as the Google search results that frustrated him so. And if Sherlock, after all this time, still doesn’t understand them, what hope does John have?

But John doesn’t seem terribly bothered. Instead, he makes a thoughtful noise and tightens his grip on Sherlock’s shirt. “Okay,” he says. “That helps. It’s okay if you don’t know exactly what you want yet, you know. That’s a good start. We can work with that.”

Then John’s right hand is dipping down his lumbar vertebrae and trailing over the healing cuts on his hip. His touch isn’t hard enough to hurt, isn’t hard enough to do anything other than remind Sherlock of them and make him wish he’d argued for something more substantial than three parallel lines.

“Will you tell me now what happened during this?” John asks, leaning back slightly.

It’s the last thing Sherlock wants to discuss now, the disaster of their last encounter, even if he knows that they’ll have to at some point. “Mind wandered,” he answers simply. “The gloves and the antiseptic. It reminded me of after I was shot, when I was in hospital. The smell, the—”

He stops, aware of John’s entire body going tense beneath him, John’s jaw clenching. Blaming himself for not seeing, not anticipating, for bringing Sherlock’s attention to the scar in the first place.

Pointless—John can hardly be blamed for the avenues that Sherlock’s mind decides to wander.

“I wanted it,” Sherlock reminds him. “Although you were meant to worship me afterwards, you realise. I had every hope you’d kiss and grope at the wounds while they healed.”

At that, John’s fingers curve and dig into Sherlock’s trousers and skin, right into the cuts, making them ache faintly, very very faintly, but still enough that Sherlock moans softly and tries to arch into the touch, craving more.

“Gorgeous,” says John, leaning back even further and tilting his head up so he’s looking up into Sherlock’s face. “I’m sorry I didn’t do that. But that’s why you should tell me what you want when I ask. Then I can be sure you get it. But… all right. Thank you for telling me now. Anyway, the point of all this, what I hope is finally starting to get through your thick bloody skull, is I’m pretty sure there’s nothing you could say or do that would put me off.”

“I have a vivid fantasy of you cutting me open and carving your name into my ribs,” Sherlock tells him, on a whim. A test of sorts.

To his surprise, John smiles fondly. “Yeah? I have a fantasy of bringing a woman home and watching her make a mess of you.”

Sherlock frowns, and something like alarm begins to beat against his sternum. “You said third parties were a hard limit.”

“They are,” John answers calmly. “That’s what makes it a fantasy. You can want something without really _wanting_ it. If anyone lays so much as a finger on you in real life, I’ll bite their whole filthy fucking hand off.”

Oh. That’s a profoundly tantalising image: John reduced to violent, primal possessiveness over Sherlock. Blood and bits of flesh on his teeth and lips. Pinning Sherlock down and fucking him while some idiot somewhere screams in agony and bleeds to death for touching what is John’s.

_John’s._

The alarm effortlessly shooed away, Sherlock folds forwards and curls himself round John again. He’s thigh-deep in the armchair now and he can scarcely feel his feet, but he doesn’t care. He’ll stay here until he’s forced to move.

“We’re all right, then?” John asks. Mumbles, really. His face buried in Sherlock’s shirt. Clinging to Sherlock nearly as tightly as Sherlock is clinging to him. “I mean, we’re not, obviously. I’m a knob who needs to remember how to trust himself, and you’re a knob who needs to learn to open his fucking mouth. There’s still loads to talk about, but—”

“Not now,” Sherlock sighs. They’ve talked enough. Sherlock rather wants to stay here, communicating in breaths and nuzzles and heartbeats, for the rest of the day.

“Mm, all right, sweetheart.”

Sherlock’s shivers in delight and relief, and they stay like that for a long while.


	6. Epilogue

Sherlock removes all the embossed, framed, and mounted _‘I want a healthy relationship’_ reminders from every room of his mind palace and replaces them with even larger _‘DON’T BE A KNOB’_ reminders, at John’s behest.

(John’s exact words, in fact, are: “If you’re determined to fixate on something I say, I’d rather it be that than something I said in a moment of panic that had nothing to do with you. And I’m not joking about the size either. I want it massive, in all capital letters, so you can read it no matter where in there you’ve got yourself lost. Go on. I’ll wait here until you’ve finished.”)

It takes ages, because Sherlock’s mind palace is expansive and he is very, very thorough, and when he is finished, he’s sure that at least one full hour has passed, possibly more. Nevertheless, John is exactly where he was before: unclothed beneath the duvet, his head and shoulders propped against the headboard of their bed, playing some sort of colourful blinky game on his phone.

Sherlock rolls towards him, grateful, and John’s left arm moves immediately so that Sherlock can duck beneath it and lie with his head on John’s pectoral.

“Finished, then?” John says.

At Sherlock’s nod, the phone is promptly shoved aside so that John can wind himself around Sherlock, shifting and situating them so that his hand is in Sherlock’s hair and Sherlock’s mouth is open against John’s scar. John’s glorious, perfect scar. Sherlock hums happily against it, marvelling at the taste and texture. If Sherlock has left a mark on John’s mind half as permanent and life-altering as the sniper bullet that left this scar, then he decides he will consider his life well-lived.

“Good,” says John. “It took you long enough. Still fancy a scratch?”

He smells overwhelmingly of silicone-based lubricant and semen. Fittingly, of course, since at some point before being ordered into his mind palace, Sherlock slathered John’s thighs in slick and fucked himself to orgasm between them.

“Of course,” Sherlock answers.

He wants it and asks for it nightly, after all, and nightly John obliges. Drags his nails painstakingly slowly up Sherlock’s back, from the fleshiest parts of his arse cheeks to the tops of his shoulders. Never following the same path he carved the previous night, never using the same degree of pressure, so that every day the scratches are different, the pattern of puffy pink lines on his back is new, and a fresh bit of skin sheds its dead cells beneath John’s nails.

Unpredictable, so that Sherlock never grows fully accustomed to the sight of John’s marks on his body.

Tonight, John keeps his scratches perfectly straight, following the line of Sherlock’s spine until he reaches Sherlock’s nape. Sherlock gasps at the sting, which is surprisingly sharp, and huddles closer, while John strokes his hair and murmurs, “There you go, sweetheart. How’s that? Good? All mine, aren’t you, love?”

_I love you_ , Sherlock thinks, toes curling in pleasure. _I love you. I love you. They’ll have to pry me from your cold dead hands, and even then I will still be yours._

“I was thinking,” John says, as Sherlock settles contentedly against him. “I might, um. Mention us, in the blog. ‘Us’ as in, not just you and me, but you and me _together_ , you know. Our relationship. Not a big production or anything, just a quick note. Not sure how you’d feel about that, though.”

How Sherlock would feel about it? Rather like he can’t wait for the next time John properly hurts him, actually. Something deep and aching that he can touch reverently when he reads the words—unpolished but earnest, John Watson in every sense—over John’s shoulder as they’re typed.

“Yes,” Sherlock says, blunt and heartfelt. “ _Yes_.”


End file.
